Multicolor mask

ABSTRACT

The invention relates to a process for forming a stacked transparent structure comprising providing a support, coating one side of said support with a multicolored mask, coating the other side of the support with a layer curable by visible light, and exposing the light-curable layer through the mask with visible light to cure the layer curable by light in exposed portions to form a cured pattern.

CROSS-REFERENCE TO RELATED APPLICATIONS

Reference is made to commonly assigned U.S. patent application Ser. No.11/437,923 filed May 19, 2006 by Irving et al. and entitled “COLOREDMASKING FOR FORMING TRANSPARENT STRUCTURES,” U.S. application Ser. No.______ (Docket 94377), filed concurrently by Irving et al. and entitled,“COLORED MASK COMBINED WITH SELECTIVE AREA DEPOSITION,” U.S. applicationSer. No. ______ (new Docket No. 94616), filed concurrently by Irving etal. and entitled “PHOTOPATTERNABLE DEPOSTION INHIBITOR CONTAININGSILOXNE,” U.S. application Ser. No. ______ (Docket 94615), filedconcurrently by Irving et al. and entitled “INTEGRATED COLOR MASK,” U.S.application Ser. No. ______ (Docket 94376), filed concurrently by Irvinget al. and entitled, “GRADIENT COLORED MASK,” U.S. application Ser. No.______ (Docket 92336A), filed concurrently by Irving et al. andentitled, “COLORED MASK FOR FORMING TRANSPARENT STRUCTURES,” and U.S.application Ser. No. ______ (Docket 94379), filed concurrently by Irvinget al. and entitled, “MULTICOLORED MASK PROCESS FOR MAKING DISPLAYCIRCUITRY,” all the above-identified applications incorporated byreference in their entirety.

FIELD OF THE INVENTION

The invention relates to a colored masking technique useful for formingelectrical components.

BACKGROUND OF THE INVENTION

Manufacture of many electronic components, including flat paneldisplays, RFID tags, and various sensing applications, relies uponaccurately patterning layers of electrically active materials applied toa relatively large substrate. These products are composed of severallayers of different patterned materials, where it is important that thelayers be in specific registration. The reasons for patterning accuracyare twofold. First of all, patterned features must be reproduced acrosslarge areas of a substrate while having precise control over theirdimensions. Secondly, products built with these features typically arecomposed of several layers of different, but interacting patternedlayers, where it is important that the layers be in specific verticalregistration, referred to as layer alignment.

Traditionally, the precise layer alignment required for fabrication ofelectronic components and devices is accomplished using conventionalphotolithography. An electrically active layer and a photoresist layerare deposited on a substrate, the position of an existing pattern on thesubstrate is detected and an exposure mask is aligned to that existingpattern. The photoresist is exposed, developed, and the electricallyactive material is etched. Small variations in temperature and humidityin this precise operation may be enough to introduce alignment errors;rigid glass substrates are used with stringent environmental controls toreduce these variations. At the other extreme, conventional printingtechniques such as offset lithography, flexography, and gravure printingalso apply multiple layers at extremely high speeds, although atsubstantially lower overlay accuracy.

There is a growing interest in advancing printing technology towardfabrication of thin film electrical components (such as TFTs) onflexible or plastic substrates. These substrates would be mechanicallyrobust, lighter weight, and eventually lead to lower cost manufacturingby enabling roll-to-roll processing. In spite of the potentialadvantages of flexible substrates, there are many issues affecting theperformance and ability to perform alignments of transistor componentsacross typical substrate widths up to one meter or more. The overlayaccuracy achievable using traditional photolithography equipment can beseriously impacted by substitution of a flexible plastic substrate forthe rigid glass substrates traditionally employed. Dimensionalstability, particularly as the process temperature approaches the glasstransition temperature (Tg) of substrate materials, water and solventswelling, anisotropic distortion, and stress relaxation are all keyparameters in which plastic supports are inferior to glass.

Typical fabrication involves sequential deposition and patterning steps.Three types of registration errors are common in these fabricationprocesses: fixed errors, scale errors, and local misalignments. Thefixed error, which refers to a uniform shift of one pattern to another,is typically dominated by the details of the motion control system.Specifically, mechanical tolerances and details of the systemintegration ultimately dictate how accurately the substrate may bealigned to a mask, or how accurately an integrated print device may bepositioned with respect to a registration mark on a moving web. Inaddition to fixed errors, scale errors may also be substantial. Errorsin pattern scale are cumulative across the substrate and arise fromsupport dimensional change, thermal expansion, and angular placementerrors of the substrate with the patterning device. Although the motioncontrol system impacts angular placement, pattern scale mismatch islargely driven by the characteristics of the support. Thermal expansion,expansion from humidity or solvent exposure, shrinkage from hightemperature exposure, and stress relaxation (creep) during storage ofthe support all contribute to pattern scale errors. Further, localpattern mismatch arising from nonisotropic deformations may also occur,particularly since the conveyance process involves applying tension. Aflexible support used in roll-to-roll manufacturing will typicallystretch in the conveyance direction and narrow in width.

There are several approaches to address the registration problem forfabrication of electronics on flexible substrates, but at this point aleading methodology has yet to emerge. Attach/detach technology has beenexplored by French et al., wherein a flexible substrate is laminated toa rigid carrier and runs through a traditional photolithographic process(I. French et al., “Flexible Displays and Electronics Made in AM-LCDFacilities by the EPLaRTM Process” SID 07 Digest, pp. 1680-1683 (2007)).Unfortunately, these technologies ultimately produce a flexibleelectronics component, but with the cost structure of current glassbased processing.

US Patent Publication No. 2006/0063351 by Jain describes coating thefront side and back side of a substrate with one or more resist layersthat may be activated simultaneously to impart distinct pattern imageswithin each resist layer. The precoated substrate is inserted between aset of prealigned masks, or alternatively a dual-wavelength masklessdirect-laser-writing lithography system is used, to simultaneouslyexpose the front and back sides.

Active alignment systems to detect previously existing patterns andcompensation schemes for deformation have also been suggested in U.S.Pat. No. 7,100,510, by Brost et al. With this approach, instead ofattaining accurate pattern overlay by maintaining tight specs on supportdimensional stability and strict environmental control, the motioncontrol system performs multiple alignments per substrate to compensatefor distortion. The proposed solution of Brost et al., to adapttraditional printing equipment for active alignment, may be viewed asexchanging the lens, mask, and lamp of a modern stepper with anintegrated print device. It is difficult to imagine significantequipment cost difference or throughput advantage, particularly if theadded task of distortion compensation is included. A fabrication costadvantage would likely come primarily from materials usage savings orremoval of expensive vacuum deposition steps.

Another approach, which would potentially enable high speed processingwith low capital investment, is to employ a self-aligning fabricationprocess. In a self-aligning process, a template for the most criticalalignments in the desired structure is applied in one step to thesubstrate and from that point forward alignment of subsequent layers isautomatic. Various methods have been described for fabricatingself-aligned TFTs. Most of these methods allow self-alignment of onelayer to another layer, but do not significantly remove the need forvery sophisticated alignment steps between several layers. For example,the gate electrode in some a-Si TFT processes is used as a “mask” toprotect the channel area from doping and laser annealing of the siliconon either side of the channel region.

The concept of self-aligned fabrication can be understood from U.S. Pat.No. 5,391,507 by Kwasnick et al, U.S. Pat. No. 6,338,988 by to Andry etal., and US Patent Publication No. 2004/229411 by Battersby.

One published technique offering the potential for a fully self alignedprocess that eliminates the need for complex registration isSelf-Aligned Imprint Lithography (SAIL), as illustrated in U.S. Pat. No.7,056,834 by Mei et al. In imprint lithography, a variable-thicknessresist is prepared on the electronically active layers and a sequencingof chemical etch and materials deposition is matched to controllederosion of the photoresist to produce TFT structures. There aredifficulties with the SAIL process. The first issue is the need for arobust nanoimprint technology for webs. Secondly, the SAIL processrequires high accuracy etch depth control, which may not be consistentwith a low cost process. Finally, a significant limitation of the SAILprocess is that layers produced by the mask cannot be fully independent.As an example, it is particularly challenging to form openings undercontinuous layers with this approach, an essential element in a matrixbackplane design.

There is a growing interest in depositing and patterning thin filmsemiconductors, dielectrics and conductors on flexible substrates,particularly because these supports would be more mechanically robust,lighter weight, and potentially lead to more economical manufacturing byallowing roll-to-roll processing. The present invention facilitateshighly accurate patterning in an advantageous and simple way that solvesone or more of the aforesaid problems in the prior art, especially whenusing flexible substrates.

PROBLEM TO BE SOLVED BY THE INVENTION

The problems addressed by the current invention are to reproducepatterned features, even across large areas, while having precisecontrol over the feature dimensions, including registration andalignment, of patterned features that are in different layers.Additionally, it is highly desirable to overcome these problems in a waythat does not require expensive equipment or expensive processes.

SUMMARY OF THE INVENTION

The invention generally is accomplished by a process for forming astacked transparent structure comprising providing a support; forming atleast a first portion of a multicolored mask on one side of saidsupport; coating the first portion of the multicolor mask with aphoto-patternable layer sensitive to visible light; and exposing thephotopatternable layer through the mask with visible light to form apattern.

One embodiment of the invention is directed to a process for forming astructure comprising:

a) providing a transparent support;

b) forming a multicolor mask having at least a first color pattern on afirst side of the support and a second color pattern; and

c) forming at least two layers of patterned functional materials, eachpatterned layer formed by:

-   -   i) coating a layer of a photopatternable material sensitive to        visible light on the first side of the support after forming the        multicolor mask;    -   ii) exposing the layer of photopatternable material through the        multicolor mask with visible light to form a photopattern        corresponding to the one of the color patterns of the multicolor        mask wherein the photopattern is composed of photopatternable        material in a second exposed state that is different from a        first as-coated state;    -   iii) depositing a layer of a functional material before or after        coating the photopatternable material; and    -   iv) patterning the functional material using the photopattern        such that the resulting patterned functional material        corresponds to the color pattern;

wherein the first color pattern, support, and at least two layers ofpatterned functional materials remain in the structure.

ADVANTAGEOUS EFFECT OF THE INVENTION

One advantage of the present invention is that it provides a method forforming aligned layers without the need for expensive alignmentequipment and processes. Another advantage is the multicolor mask isprepared directly on the support in color-encoded form ensuring that thecorrect mask is used. Additionally, spectrally-sensitized resistmaterials, sensitive to either red, green or blue light can be used topattern all layers in a transistor, including a transparent oxide suchas a zinc-oxide-containing semiconductor. The multicolor mask has theadvantage of containing more independently addressable levels than agrayscale mask and works particularly well for patterning transparentelectronic materials.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features, and advantages of the presentinvention will become more apparent when taken in conjunction with thefollowing description and schematic drawings wherein identical referencenumerals have been used, where possible, to designate identical oranalogous features that are common to the figures, and wherein:

FIGS. 1 and 1A are a pattern of blue color absorber on a transparentsupport;

FIGS. 2 and 2A shows a pattern of green color absorber on a transparentsupport;

FIGS. 3 and 3A. shows a pattern of red color absorber on a transparentsupport;

FIGS. 4 and 4A show the individual color absorber layers in a layeredstructure on support material forming a multicolor mask;

FIGS. 5A-5D show a process for selectively forming a pattern of materialregistered with the blue color absorber pattern of the multicolor mask;

FIGS. 6A-6D show a process for selectively forming a pattern of materialregistered with the green color absorber pattern of the multicolor mask;

FIGS. 7A-7D show a process for selectively forming a pattern of materialregistered with the red color absorber pattern of the multicolor mask;

FIGS. 8A-8H show a process where three different patterned structuresare selectively formed by changing the color of exposing light throughthe multicolor mask;

FIGS. 9A-9F show an example of a liftoff patterning process using amulticolor mask;

FIGS. 10A-10F show an example of a selective etch patterning processusing a multicolor mask;

FIGS. 11A-11F show a selective deposition patterning process using amulticolor mask;

FIG. 12A-12H shows a possible sequence of exposure, processing, anddeposition steps to form a multilayer electronic device usingtransparent components and a multicolor mask;

FIG. 13A-13H shows another possible sequence of exposure, processing,and deposition steps to form a multilayer electronic device usingtransparent components and a multicolor mask;

FIG. 14A-14H shows yet another possible sequence of exposure,processing, and deposition steps to form a multilayer electronic deviceusing transparent components and a multicolor mask;

FIGS. 15A-15B illustrate another embodiment of a multicolor mask of thepresent invention; and

FIGS. 16, 16A, and 16B show another embodiment of a layer electronicdevice formed using a multicolor mask of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

For ease of understanding, the following terms used herein are describedbelow in more detail.

As utilized herein, the term “front” as applied to the invention articleis the side of the support carrying the functional patterned layers; theterm “back” as used herein refers to the side of the support opposite tothe side carrying the patterned functional layers.

“Vertical” means substantially perpendicular to the surface of asubstrate.

“Transparent” generally denotes a material or construct that does notabsorb a substantial amount of light in the visible portion (and/orinfrared portion in certain variants) of the electromagnetic spectrum.In this invention, the transparency of a materials is only withreference to the colors of light that are being used in a particularprocess step. Transparent means at least 65% of the reference lightpasses through the member.

“Photopatternable” refers to a material that, upon exposure to light,changes in states such as in terms of solubility, tackiness, mechanicalstrength, permeability to etchants or gases, surface reactivity and/orindex of refraction, such that the changed material corresponds to apattern.

“Positive” refers to a pattern, which contains material in those areasabove the colored parts of the photomask.

“Negative” refers to a pattern, which contains material in those areasabove the transparent parts of the photomask.

“Multicolor mask” refers to the vertically aligned set of colorabsorbing patterns in the patterned structure. The color patterns of amulticolor mask may be in separate layers or in the same layer.

A thin film transistor (TFT) is a likely electronic element that canbenefit from the patterning process of this invention. The next threedefinitions refer specifically to thin film transistors.

As used herein, the terms “over,” “above,” and “under” and the like,with respect to layers in the thin film transistor, refer to the orderof the layers with respect to the support, but do not necessarilyindicate that the layers are immediately adjacent or that there are nointermediate layers.

“Gate” generally refers to the insulated gate terminal of a threeterminal FET when used in the context of a transistor circuitconfiguration.

The preceding term descriptions are provided solely to aid the reader,and should not be construed to have a scope less than that understood bya person of ordinary skill in the art or as limiting the scope of theappended claims.

The process of this invention can be used to generate any variety ofmultilayer structures containing patterned layers with fixed verticalregistration. This process is therefore capable of producingmonolithically integrated structures that can be designed to function asconductors, inductors, capacitors, transistors, diodes, photodiodes,light emitting diodes, and other electronic or optoelectroniccomponents. Furthermore, the patterning technology can be used tosimultaneously produce a number of these devices arranged in a way toproduce useful electronic circuitry.

Accurate pattern overlay over large areas and on flexible supports isenabled by use of a color-encoded mask, which is prepared directly onthe support, in combination with spectrally sensitized photoresists. Thecolor-encoded mask can contain either in one structure, or in multipleportions, all or most of the patterning information for the system.Transparent electronic materials are subsequently deposited inlayer-by-layer fashion. Spectrally sensitized photoresists areselectively exposed through the multicolored mask to form photoresistpatterns on the front side of the support, vertically aligned to thecolor mask. Patterning of electrically active or functional layers canbe accomplished by using etch, liftoff, or selective deposition processto pattern the gate, dielectric, semiconductor, and source/drain layers.The multicolor mask is part of the substrate, and is formed on eitheronly the side of the active layers or on both sides of the substrate.The multicolor mask can contain pattern information for all of thelayers in a process. Fabrication using the present invention can befully self-aligning, and catastrophic overlay errors arising fromdimensional change of supports, web weave, and transport errors canthereby be avoided.

In one embodiment of the present invention, the entire multicolor maskremains as part of the final device. In another embodiment of theinvention, only a first portion of the multicolor mask remains in thefinal device. These embodiments will be better understood with respectto the figures.

The figures and following description illustrate a masking scheme of thecurrent invention. The illustrative example of this description utilizesthree masking layers, composed of different color absorbing materials,and utilizes photopatternable materials, sensitive to colored light, topattern transparent functional layers. The figures are intended toillustrate the present invention and should not be considered limiting.Multicolor masks of two masking layers, as well as multicolor masks ofgreater than three masking layers are alternative embodiments of thepresent invention. Additionally, the figures illustrate the colorpatterns of the multicolor mask as separate layers for descriptiveclarity. In other embodiments of the present invention, all of the colorpatterns to reside in a single layer can be easily understood withrespect to the figures in this disclosure. Furthermore, embodimentswhere a multiple, but not all, color patterns are in a single layer fallwithin this invention.

Light used for exposing can be panchromatic or colored. Panchromaticlight refers to light that has some spectral intensity over the visiblespectrum. Panchromatic light should be recognized by one skilled in theart as light is a light that contains multiple colors. Colored lightgenerally refers to light that has high intensity in certain spectralregions and lower intensities in others. Colored light can be describedby the wavelength of the maximum intensity (λ_(max)) and by the FWHM(full width at half the maximum), or by the bandpass. For light to beconsidered colored, the ratio of the minimum intensity to the maximumintensity across a given spectral region should be less than 20%,preferably less than 10%.

Referring now to the drawings, FIGS. 1-3A show the patterns of threemask layers. FIG. 1 and 1A show the pattern of the first mask layer as apattern of a blue color absorber (14) on transparent support (12). FIG.2 and 2A show the pattern of the second mask layer as a pattern of agreen color absorber (18) on transparent support (12). FIG. 3 and 3Ashow the pattern of the third mask layer as a pattern of a red colorabsorber (16) on transparent support (12). FIGS. 4 and 4A show anarticle 11 composed of individual color absorber layers (14, 16, 18) ina layered structure on support material forming multicolor mask (10). Animportant aspect of the present invention is that the multicolor maskcontains in one structure most or all of the patterning information forthe system in a color-encoded form. This is important because the entirearticle, including support (12) may be exposed to varying temperature,pressure, solvent and humidity treatments during the fabrication andcoating steps, naturally leading to variations in dimension (such asshrinkage or thermal expansion) of the support. Web transport systemsapply tension to the support, leading to dimensional instability aswell. In fact, the lowest cost and potentially cheapest supportmaterials are likely to have a higher degree of dimensional instability.For example, polyester film has a thermal expansion coefficient of0.0018% per ° C., such that a 5° C. change will result in a dimensionalchange of 90 μm over 1 meter. The effect of humidity expansion andthermal expansion need not lead to cumulative and catastrophic alignmenterrors when a multicolor mask element (10) is provided. Simply, thepatterning information is contained in the color absorbing layers thatare attached to the support, and thus remain in fixed vertical alignmentas the support shrinks or expands and are not impacted by supportdimensional change.

FIGS. 5A-7D show processes for selectively forming patterns ofphotopatternable material registered with a specific color absorberpattern of multicolor mask (10). The specific pattern to be formed isselected by adjusting the sensitivity distribution of thephotopatternable film. A photopatternable layer with a sensitivity toblue, green, or red light is coated on the multicolor mask. Thisphotopatternable layer is exposed with light through the multicolormask. The color absorbers of the multicolor mask selectively transmitthe illuminating light, thereby exposing the photopatternable layer to apattern of colored light. For example, a cyan mask absorbs red lightwhile transmitting blue and green light. Similarly, a magenta maskabsorbs green light while transmitting red and blue light and a yellowmask absorbs blue light while transmitting red and green light. Thus, bycombining the properties of such individual masks, a multicolor mask maybe formed to provide patterns of selectively transmitted light. Thesensitivity distribution of the photopatternable layer, in a preferredembodiment, is completely contained within the absorption spectrum ofone of the color absorbing materials used in multicolor mask (10) andcompletely isolated from the absorption spectrum of the other colorabsorbing materials in multicolor mask (10). In a preferred embodimentof the invention, the photopatternable layer contains a polymerizablecompound and a photoinitiator responsive only to specific wavelengths ofcolored light. Absorption of colored light by the photoinitiatorinitiates the photopolymerization reaction. The photopatternable layermay contain additional components that include but are not limited topolymeric binders, fillers, pigments, surfactants, adhesion modifiers,antioxidants, co-initiators, chain transfer agents, and the like. Oneconvenient way to modify the sensitivity distribution of thephotopatternable layer is with the identity of the photoinitiator. Thespectral distribution of illuminating light may be specifically selectedto minimize effects from unwanted absorption of the color absorbingmaterial and/or unwanted sensitivity of the photopatternable layer.Following exposure, the photopatternable layer is developed. Theremaining pattern may be the positive image of the mask layer or anegative image, depending on the type of photopatternable material used.FIGS. 5A-7D illustrate the use of a photocurable or negative workingphotoresist.

FIGS. 5A-5D show a process for selectively forming a pattern of materialregistered with the blue color absorber pattern of the multicolor mask.Referring now to FIGS. 5A and 5B,there is illustrated a schematic planview and cross-sectional view of the multicolor mask (10) that has beencoated with a blue photopatternable layer (22) and exposed with a lightsource containing blue light. This light source may be a white light, orpanchromatic light, source. In this embodiment, the photopatternablematerial of the photopatternable layer is negative working. FIGS. 5C and5D show the schematic plan view and cross-sectional view of theresulting structure after the exposed blue-curable film from FIG. 5A hasbeen developed, forming a pattern of blue-cured material (24) registeredwith the blue color absorber pattern (14) of multicolor mask (10).

FIGS. 6A-6D show a process for selectively forming a pattern of materialregistered with the green color absorber pattern of the multicolor mask.FIGS. 6A and 6B show schematic plan view and cross-sectional view of themulticolor mask (10) that has been coated with a green photopatternablelayer (30) and exposed with a light source containing green light. Thislight source may be a white light, or panchromatic light, source. Inthis embodiment, the photopatternable material of the photopatternablelayer is negative working. FIGS. 6C and 6D show a schematic plan viewand cross-sectional view of the resulting structure after the exposedgreen-curable film from FIG. 6A has been developed, forming a pattern ofgreen-cured material (32) registered with the green color absorberpattern (18) of multicolor mask (10).

FIGS. 7A-7D show a process for selectively forming a pattern of materialregistered with the red color absorber pattern of the multicolor mask.FIGS. 7A and 7B show a schematic plan view and cross-sectional view ofthe multicolor mask (10) that has been coated with a red curable film(38) and exposed with a light source containing red light. This lightsource may be a white light, or panchromatic light, source. In thisembodiment, the photopatternable material of the photopatternable layeris negative working. FIGS. 7C and 7D show a schematic plan view andcross-sectional view of the resulting structure after the exposedred-curable film from FIG. 7A has been developed, forming a pattern ofred-cured material (40) registered with the red color absorber pattern(16) of multicolor mask (10).

FIGS. 8A-8H show a process where three different patterned structuresare selectively formed by changing the color of exposing light throughthe multicolor mask and employing a film 44 curable with panchromaticlight. The pan-curable film may be formulated, for example, whichcontains a polymerizable compound and a mixture of red, green, and blueresponsive photoinitiators. When a pan-curable film is used with thepresent invention, the specific pattern to be formed is selected byadjusting the spectral energy distribution of the exposing light.Therefore, the absorption spectrum of the color absorbing material forthe intended pattern should match the wavelength of exposing light.FIGS. 8A-8H also serve to illustrate another embodiment of the presentinvention. Multicolor mask 10 may optionally have a transparent coating50 on the top surface. The transparent coating 50 may have insulating,smoothing, planarizing or other properties which improve the performanceof the end device that will be formed over the multicolor mask 10. FIGS.8A-8H illustrate the present invention using negative-actingphotopatternable materials; one skilled in the art will understand thatthe present invention may also be used with positive-acting materials.FIGS. 8A and 8B show a schematic plan view and cross-sectional view ofthe multicolor mask (10), which has been coated with a filmphotopatternable with panchromatic light (44).

FIGS. 8C and 8D show a schematic plan view and cross-sectional view ofthe resulting structure after the film photopatternable withpanchromatic light (44) from FIG. 8A has been exposed with blue lightand developed, forming a pattern of cured pan-photopatternable material(46) registered with the blue color absorber pattern (14) of multicolormask (10).

FIGS. 8E and 8F show a schematic plan view and cross-sectional view ofthe resulting structure after the film photopatternable withpanchromatic light (44) from FIG. 8A has been exposed with green lightand developed, forming a pattern of cured pan-photopatternable material(46) registered with the green color absorber pattern (18) of multicolormask (10).

FIGS. 8G and 8H show a schematic plan view and cross-sectional view ofthe resulting structure after the film photopatternable withpanchromatic light (44) from FIG. 8A has been exposed with red light anddeveloped, forming a pattern of cured pan-photopatternable material (46)registered with the red color absorber pattern (16) of multicolor mask(10). It will be readily understood that combinations of patterns shownin FIGS. 8C-8H are possible simply by tuning the color of exposing light(i.e. a blue-plus-green light exposure will cure both shaded regions(46) shown in FIG. 8C and 8E).

An important aspect of this invention is the ability to use one of thecolor patterns of the multicolor mask to form an aligned pattern of afunctional material on at least a portion of the multicolor mask. Anumber of methods can be used to cause this patterning. Therefore, bothfunctional materials and photopatternable materials are applied to themulticolor mask and patterned using colored light. General classes offunctional materials that can be used include conductors, dielectrics orinsulators, and semiconductors. The spectral distribution ofilluminating light is modulated by the transmittance of all previouslyapplied and patterned layers. For the purposes of this discussion, themulticolor mask (10) is defined as including all color absorbingportions of the patterned structure with the exception of thephotopatternable film. Because the colored light photopatterning processdescribed above and illustrated sing FIGS. 5A-8H results in a change inpermeability, solubility, tackiness, mechanical strength, surfacereactivity, or index of refraction of the photopatterned material, theseproperties may be exploited in subsequent fabrication steps.Particularly useful methods to pattern functional and electronicmaterials using this invention are referred to as liftoff, selectiveetch, and selective deposition processes.

FIGS. 9A-9F show the operation of this system using a liftoff patterningprocess. FIGS. 9A and 9B show a schematic plan view and cross-sectionalview of the multicolor mask (10) with a pattern of photopatternedmaterial (46) registered with green color absorber pattern (18).Referring now to FIGS. 9C and 9D, a uniform coating of transparentfunctional material (48) is applied over the pattern of photopatternedmaterial (46). FIGS. 9E and 9F show the final step in a liftoff sequencewhen the cured material (46) and portions of transparent functionalmaterial on top of the cured material are removed. This is accomplished,for example, by treating the sample with a material that selectivelyattacks the remaining cured material under the functional material. Thisleaves functional material where there was originally no photopatternedmaterial.

FIGS. 10A-10F show the operation of this system embodiment using aselective etch patterning process. FIGS. 10A and 10B show a schematicplan view and cross-sectional view of multicolor mask (10) with auniform coating of transparent functional material (48) under a patternof cured material (46) registered with green color absorber pattern(18). FIGS. 10C and 10D illustrate a subsequent step after the exposedportions of transparent functional material are removed in an etchprocess. The sample is exposed to a material that attacks or dissolvesthe functional layer. Regions of transparent functional materialprotected by the pattern of cured material (46) are not removed in theetch step. The pattern of transparent functional material (48) isregistered with the pattern of cured material (46) and is alsoregistered with green color absorber pattern (18).

Referring now to FIGS. 10E and 10F there is illustrated the resultingstructure after the pattern of cured material (46) is removed. This maybe accomplished, for example, with a compatible solvent or oxygen plasmatreatment.

FIGS. 11A-11F show the operation of this system using a selectivedeposition patterning process embodiment. A number of depositionprocesses employing both liquids and vapor phase chemical delivery canbe tailored to operate in a manner where material selectively depositsonly in certain areas. For example, FIGS. 11A and 11B show multicolormask (10) with a pattern of cured material (46) registered with greencolor absorber pattern (18). FIGS. 11C and 11D illustrate a subsequentstep after a transparent functional material (48) is selectivelydeposited on regions of support (12) that are not covered by the patternof cured material (46). Referring now to FIGS. 1E and 1F a subsequentstep is illustrated where the pattern of cured material (46) is removedby treating entire to attack the remaining cured material. The patternof transparent functional material (48) is registered with the greencolor absorber pattern (18).

FIGS. 12A-14H show a possible sequence of exposure, processing, anddeposition steps that would allow construction of a multilayerelectronic device as seen in FIGS. 14G and 14H.

FIGS. 12A-12H illustrate one embodiment of the coating and patterningsteps for a first transparent layer of an electronic device using a bluephotopatternable coating and a selective etch process. FIGS. 12A and 12Bshow multicolor mask (10) coated with a first transparent functionalmaterial (20) and a blue photopatternable material (22). This structureis exposed with a light source containing blue light. By way ofillustration, the functional material (20) could be a transparentconducting oxide material such as ITO or aluminum doped ZnO. Because thephotopatternable coating (22) drawn in this structure is sensitive onlyto blue light, the light source may be a white light source, or acolored light source containing blue light.

Referring now to FIGS. 12C and 12D, there is illustrated the resultingstructure after the exposed blue photopatternable film has beendeveloped, forming a pattern of blue cured material (24) registered withthe blue color absorber pattern (14) of multicolor mask (10). FIGS. 12Eand 12F show an etch step where exposed portions of transparentfunctional material (20) are removed in, for example, an acid bath,forming a pattern of transparent functional material (26) registered tothe blue color absorber pattern (14) of multicolor mask (10). FIGS. 12Gand 12H show the structure of FIG. 12E after the pattern of blue curedmaterial (24) is removed using, for example, an oxygen plasma treatment.

FIGS. 13A-13H illustrate the coating and patterning steps for the secondtransparent layer of the electronic device using a green curable coatingusing a selective etch process. Alternatively, the second transparentlayer could be patterned be a selective deposition process, a liftoffprocess, or a light curing process. FIGS. 13A and 13B show themulticolor mask (10), including the first patterned transparent layer,coated with a uniform layer of transparent functional material (28) anda green photopatternable layer (30). This structure is exposed with alight source containing green light. By way of example, the transparentfunctional material (28) could be a dielectric material such as aluminumoxide or alternatively a semiconducting layer such as zinc oxide. Thismaterial could be a dielectric or semiconducting layer precursor that isconverted in an annealing step to form the electrically functionalmaterial. Multiple layers of transparent functional layers couldpotentially be coated at this step. By way of example, a transparentcoating of a dielectric material could be first applied and a secondtransparent coating of semiconductor material could be subsequentlyapplied. Because the photopatternable coating (30) shown in FIGS. 13Aand 13B is sensitive only to green light, the light source may be awhite light source, or a colored light source containing green light.FIGS. 13C and 13D show the resulting structure after the exposed greenphotopatternable material (30) from FIGS. 13A and 13B has beendeveloped, forming a pattern of green cured material (32) registeredwith the green color absorber pattern (18) of multicolor mask (10).

Referring now to FIGS. 13E and 13F, there is illustrated the structureof FIG. 13C after the exposed portions of transparent functionalmaterial (28) are removed in an etch step, forming a pattern oftransparent functional material (34) registered to the green colorabsorber pattern (18) of multicolor mask (10). FIGS. 13G and 13H showthe structure of FIG. 13E after the pattern of green cured material (32)is removed using, for example, an oxygen plasma treatment.

FIGS. 14A-14H illustrate the coating and patterning steps for the thirdtransparent layer of the electronic device using a red curable coatingusing a selective etch process. Alternatively, the third layer could bepatterned with a selective deposition process, a liftoff process, or alight curing process. FIGS. 14A and 14B show the multicolor mask (10),including the first and second patterned transparent layers, coated witha uniform layer of transparent functional material (36)and ared-photopatternable material (38). This structure is exposed with alight source containing red light. By way of example, the transparentfunctional material (36) could be a layer of indium-tin oxide or silvernanoparticles. Because the photopatternable coating (38) drawn in thisstructure is sensitive only to red light, the light source may be awhite light source, or a colored light source containing red light.FIGS. 14C and 14D show the resulting structure after the exposed redphotopatternable material (38) from FIG. 14A has been developed, forminga pattern of red cured material (40) registered with the red colorabsorber pattern (16) of multicolor mask (10). Referring now to FIGS.14E and 14F, there is illustrated the structure of FIG. 14C after theexposed portions of transparent functional material (36) are removed inan etch step, forming a pattern of transparent functional material (42)registered to the red color absorber pattern (16) of multicolor mask(10). FIGS. 14G and 14H show the structure of FIG. 14E after the patternof red cured material (40) is removed. In this multilayer structure, thepattern of transparent functional material (26) is registered to theblue color absorber pattern (14) of multicolor mask (10). The pattern oftransparent functional material (34) is registered to the green colorabsorber pattern (18) of multicolor mask (10). The pattern oftransparent functional material (42) is registered to the red colorabsorber pattern (16) of multicolor mask (10).

FIGS. 15A and 15B illustrate alternative arrangements of multicolor mask10 according to the present invention. In these embodiments, multicolormask 10 is made up of a first mask portion 120 formed on the first sideof substrate and a second mask portion 122 formed on the backside of thesubstrate.

This alternative arrangement has the advantage of allowing for theremoval of a portion of the multicolor mask. The first mask portion 120will remain in the final device, while the second mask portion 122 maybe removed after completion of the final device. This may particularlyuseful in display devices that are viewed through the transparentsubstrate. The use of these alternative multicolor mask structuresshould be easily understood with respect to the previous Figures.

FIGS. 16 and 16A are analogous to FIGS. 14G and 14H and illustrate acompleted device formed using a multicolor mask with a first maskportion 120 formed on the first side of substrate and a second maskportion 122 formed on the backside of the substrate. FIG. 16Billustrates the completed device after the additional step of removingthe second mask portion.

An important aspect of the present invention is the multicolor mask cancontain in one structure most or all of the patterning information forthe system. This multicolor mask can be generated by any method thatproduces an image containing the desired colors with sufficientprecision and registration for the anticipated application.

The different color absorbers in the multicolored mask may besequentially or simultaneously deposited and patterned by many methods.One method to produce the multicolor mask is to print the mask usinginks containing dyes or pigments with the appropriate spectralqualities. Inks used in the printing could be of any common formulation,which would typically include the colorant material along with a vehicleor solvent, binders, and surfactants. Examples of such multicolorprinting systems are inkjet printing, gravure printing, flexography,offset lithography, screen or stencil printing, and relief printing.Color thermographic printing may be used to produce the different colorabsorbing layers on the support. Thermochromic compounds, bleachabledyes, heat decomposable compounds, or chemical color formers may be usedto form the different color absorbing layer patterns on the support. Thedifferent color absorbers may be applied to the support using a laser orthermal transfer process from a donor sheet. Alternately, the colorabsorbing patterns may be produced on the support by an ablativerecording process.

Particularly useful color absorbers are those materials with maximumabsorption in a selected portion of the visible band and maximumtransmission in remaining portions. So-called block-type dyes and cutofffilter materials are ideal for use in the multicolor mask. The differentcolor absorbers may be applied in any convenient order, or applied in asingle layer dispersed in a binder. A receiving layer for colorabsorbing materials may optionally be coated on the back side of thesupport before the color absorbing materials are applied.

The different color absorbers in the multicolor mask may be formed by aphotolithographic method using, for example, dyed photocurable coatings,such as pigmented or dyed photoresist.

It may be particularly convenient and cost effective to produce areusable master image for subsequent duplication on the main substrate.In this embodiment, a master mask image is produced of very highaccuracy and resolution. This may be accomplished with any of the abovetechniques. Preferably, this would be done with a photolithographicmethod that allows a very high quality master image to be produced. Itmay even be preferable to produce the master image upon a rigidtransparent substrate in order to achieve highly accurate verticalalignment between color absorbing layers. The color information in themaster color image can be reproduced on the main substrate using a colorduplicating or color copying process. For negative-working duplicationprocesses, the master color image would be provided as a negative copyof the multicolor mask.

In a traditional photolithographic process for large area electronicdevice fabrication, excellent alignment must be achieved over very largeareas. In the above method of master duplication, the master may beconsiderably smaller and thus easier to fabricate, but then duplicatedon the final substrate in a replicating pattern so as to cover a largerarea. Although this method of stepping is used for individual masklayers in a conventional photolithographic process, in those processesexcellent alignment is still required within the stepping operation. Inthe current inventive process, considerable tolerance can exist in thelocation of the individual duplications, since each will contain all therequired information for a multilayer pattern.

Color image capture processes employing light sensitive materials may beused to reproduce the master color image. The light sensitive layers canbe composed of any set of materials capable of capturing a multicolorlight pattern and subsequently being treated or developed in a way toproduce a color pattern. Examples of such multicolor image capturematerials are color negative photographic imaging layers, color reversalphotographic imaging layers, color photothermographic imaging layers,Cycolor® imaging layers, and diffusion transfer color photographicimaging layers such as color instant films, and color Pictrography®film. A master color image may alternatively be reproduced on the mainsubstrate using a color duplicating or copying process such as colorelectrophotography.

The multicolor mask can be produced on a separate roll of material andthen laminated to the substrate. Preferably the lamination is done withthe image side of the mask opposite the substrate and that the maskimage is as close as possible to the functional layers to be patterned.For embodiments with a portion of the mask on the back side of thesubstrate, the lamination should be done such that the mask image is asclose to the substrate as possible.

It may be particularly advantageous for optical considerations to coatthe main support layer directly onto the color absorbing layers of themulticolor mask. In this embodiment, the color absorbing layers could bepatterned on a carrier support roll and then the main support layercould be cast directly onto the color absorbing layers.

Alternately, the color absorbing layers can be patterned on a separate(donor) roll of material and then all of the color absorbing layers canbe transferred in a single step from the donor roll onto the mainsubstrate.

The multicolor mask layers may be separated from the electronicallyactive layers by a barrier layer. Depending on the application, it maybe preferable to place the color layers on the back of a thin support sothey may be bleached or removed at the end of the fabrication process,and will not create planarity and contamination problems for the activedevice layers. As noted above, having a portion of the multicolor maskon the device side of the substrate, and a portion on the backside forpotential removal is advantageous for some devices. Therefore, itimportant to understand the resolution limit for a remotely exposedphotoresist layer. This type of exposure is referred to as a proximityexposure in traditional photolithography. In proximity mode, the maskdoes not contact the wafer, so there are resolution losses due todiffraction effects. A useful discussion of resolution in this so-calledproximity printing mode can be found in “Photoreactive Polymers: TheScience and Technology of Resists” by A. Reiser, Wiley-Interscience,John Wiley & Sons, 1989, pp. 234-246.

The diffraction effect in proximity printing limits the minimum featuregap on the mask as described by Equation (1):

W_(min)≈√{square root over (kλS)} k≈1   Equation (1)

where W_(min) is the minimum feature gap on the mask, λ is the exposurewavelength, and S is the separation between the mask and the wafer.Similarly, the minimum line/gap period is given by the relationship:

$\begin{matrix}{{2b_{\min}} = {3\sqrt{\lambda\left( {s + \frac{z}{2}} \right)}}} & {{Equation}\mspace{20mu} (2)}\end{matrix}$

where b_(min) is the minimum line gap period, λ is the exposurewavelength, s is the separation between the mask and the wafer, and z isthe resist thickness.

These models indicate that even for a 100 μm distance typical forflexible supports, 6-8 μm features are resolvable, depending on theexposure wavelength. Again at the 100 μm distance, a line/gapperiodicity in the range 9-12 μm should be resolvable, depending on theexposure wavelength. In the case of front-side masking, the barrierthickness is also highly tunable. Table A below uses Equations (1) and(2) to predict the minimum feature size and periodicity as a function ofthe mask and resist separation. Examples using 365 nm or 650 nm exposinglight are shown as representative of the two ends of the visiblespectrum.

TABLE A Mask and Exposing resist layer separation wavelength 1 μm 10 μm100 μm (nm) separation separation separation W_(min) minimum 365 0.6 2 6resolvable gap (μm) 650 0.8 2.5 8 b_(min) minimum 365 1.1 3 9 resolvable650 1.5 4 12 periodicity (μm)

Based on these models, the multicolor mask can be designed to meet theresolution and transparency requirements of the final device.

Many polymers can be caused to vary their properties by exposure tolight, and thus be useful as photopatternable layers. Many typical lightsensitive polymers are only sensitive to UV and deep UV radiation.Preferably the photopatternable materials for this invention arerendered sensitive to visible light.

A variety of photopolymerization systems that are activated by visibleradiation have been developed. A useful discussion of UV curable andvisible light photopatternable materials can be found in “PhotoreactivePolymers: The Science and Technology of Resists” by A. Reiser,Wiley-Interscience, John Wiley & Sons, 1989, pp. 102-129. U.S. Pat. No.4,859,572 by Farid et al., incorporated here by reference, describes aphotographic imaging system, which relies on using visible light toharden an organic component and produce an image pattern. This referencedescribes a variety of suitable visible light sensitive photoinitiators,monomers, and film formulation guidelines for use in thephotopatternable layers of this invention.

Sensitivity to visible light can be accomplished by the use ofpolymerizable compound along with a photopolymerization initiator. In apreferred embodiment of the invention, the photosensitive resistcontains a polymerizable compound selected from among compounds havingat least one, preferably two or more, ethylenically unsaturated bond atterminals. Such compounds are well known in the industry and they can beused in the present invention with no particular limitation. Suchcompounds have, for example, the chemical form of a monomer, aprepolymer, i.e., a dimer, a trimer, and an oligomer or a mixture and acopolymer of them. As examples of monomers and copolymers thereof,unsaturated carboxylic acids (e.g., acrylic acid, methacrylic acid,itaconic acid; crotonic acid, isocrotonic acid, maleic acid, etc.), andesters and amides thereof can be exemplified, and preferably esters ofunsaturated carboxylic acids and aliphatic polyhydric alcohol compounds,and amides of unsaturated carboxylic acids and aliphatic polyhydricamine compounds are used. In addition, the addition reaction products ofunsaturated carboxylic esters and amides having a nucleophilicsubstituent such as a hydroxyl group, an amino group and a mercaptogroup with monofunctional or polyfunctional isocyanates and epoxies, andthe dehydration condensation reaction products of these compounds withmonofunctional or polyfunctional carboxylic acids are also preferablyused. The addition reaction products of unsaturated carboxylic estersand amides having electrophilic substituents such as an isocyanato groupand an epoxy group with monofunctional or polyfunctional alcohols,amines and thiols, and the substitution reaction products of unsaturatedcarboxylic esters and amides having releasable substituents such as ahalogen group and a tosyloxy group with monofunctional or polyfunctionalalcohols, amines and thiols are also preferably used. As anotherexample, it is also possible to use compounds replaced with unsaturatedphosphonic acid, styrene, vinyl ether, etc., in place of theabove-unsaturated carboxylic acids.

Specific examples of ester monomers of aliphatic polyhydric alcoholcompounds and unsaturated carboxylic acids include, as acrylates,ethylene glycol diacrylate, triethylene glycol diacrylate,1,3-butanediol diacrylate, tetramethylene glycol diacrylate, propyleneglycol diacrylate, neopentyl glycol diacrylate, trimethylolpropanetriacrylate, trimethylolpropane tri(acryloyloxypropyl)ether,trimethylolethane triacrylate, hexanediol diacrylate,1,4-cyclohexanediol diacrylate, tetraethylene glycol diacrylate,pentaerythritol diacrylate, pentaerythritol triacrylate, pentaerythritoltetraacrylate, dipentaerythritol diacrylate, dipentaerythritolhexaacrylate, sorbitol triacrylate, sorbitol tetraacrylate, sorbitolpentaacrylate, sorbitol hexaacrylate, tri(acryloyloxyethyl)isocyanurate, polyester acrylate oligomer, etc. As methacrylates,examples include tetramethylene glycol dimethacrylate, triethyleneglycol dimethacrylate, neopentyl glycol dimethacrylate,trimethylolpropane trimethacrylate, trimethylolethane trimethacrylate,ethylene glycol dimethacrylate, 1,3-butanediol dimethacrylate,hexanediol dimethacrylate, pentaerythritol dimethacrylate,pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate,dipentaerythritol dimethacrylate, dipentaerythritol hexamethacrylate,sorbitol trimethacrylate, sorbitol tetramethacrylate, andbis[p-(3-methacryloxy-2-hydroxy-propoxy)phenyl]dimethylmethane,bis[p-(methacryloxyethoxy)-phenyl]dimethylmethane. As itaconates,examples include ethylene glycol diitaconate, propylene glycoldiitaconate, 1,3-butanediol diitaconate, 1,4-butanediol diitaconate,tetramethylene glycol diitaconate, pentaerythritol diitaconate, andsorbitol tetraitaconate. As crotonates, examples include ethylene glycoldicrotonate, tetramethylene glycol dicrotonate, pentaerythritoldicrotonate, and sorbitol tetradicrotonate. As isocrotonates, examplesinclude ethylene glycol diisocrotonate, pentaerythritol diisocrotonate,and sorbitol tetraisocrotonate. As maleates, examples include ethyleneglycol dimaleate, triethylene glycol dimaleate, pentaerythritoldimaleate, and sorbitol tetramaleate. Further, the mixtures of theabove-described ester monomers can also be used. Further, specificexamples of amide monomers of aliphatic polyhydric amine compounds andunsaturated carboxylic acids include methylenebis acrylamide,methylenebis-methacrylamide, 1,6-hexamethylenebis-acrylamide,1,6-hexamethylenebis-methacrylamide, diethylenetriaminetris-acrylamide,xylylenebis-acrylamide, and xylylenebis-methacrylamide.

Further, urethane-based addition polymerizable compounds which areobtained by the addition reaction of an isocyanate and a hydroxyl groupare also preferably used in the present invention. A specific example isa vinyl urethane compound having two or more polymerizable vinyl groupsin one molecule, which is obtained by the addition of a vinyl monomerhaving a hydroxyl group represented by the following formula (V) to apolyisocyanate compound having two or more isocyanate groups in onemolecule.

CH₂═C(R)COOCH₂CH(R′)OH

wherein R and R′ each represents H or CH₃.

Other examples include polyfunctional acrylates and methacrylates, suchas polyester acrylates, and epoxy acrylates obtained by reacting epoxyresins with (meth)acrylic acids. Moreover, photo-curable monomers andoligomers listed in Sartomer Product Catalog by Sartomer Company Inc.(1999) can be used as well.

Depending upon the final design characteristics of the photosensitivematerial, a suitable addition polymerizable compound or combination ofaddition polymerizable compounds, having the desired structure andamounts can be used. For example, the conditions are selected from thefollowing viewpoint. For the photosensitive speed, a structurecontaining many unsaturated groups per molecule is preferred and in manycases bifunctional or more functional groups are preferred. Forincreasing the strength of an image part, i.e., a cured film,trifunctional or more functional groups are preferred. It is effectiveto use different functional numbers and different polymerizable groups(e.g., acrylate, methacrylate, styrene compounds, vinyl ether compounds)in combination to control both photosensitivity and strength. Compoundshaving a large molecular weight or compounds having high hydrophobicityare excellent in photosensitive speed and film strength, but may not bepreferred from the point of development speed and precipitation in adeveloping solution. The selection and usage of the additionpolymerizable compound are important factors for compatibility withother components (e.g., a binder polymer, an initiator, a functionalmaterial, etc.) in the photopolymerization composition. For example,sometimes compatibility can be improved by using a low purity compoundor two or more compounds in combination. Further, it is also possible toselect a compound having specific structure for the purpose of improvingthe adhesion property of a support, a functional material, and anovercoat layer. Concerning the compounding ratio of the additionpolymerizable compound in a photopolymerization composition, the higherthe amount, the higher the sensitivity. But, too large an amountsometimes results in disadvantageous phase separation, problems in themanufacturing process due to the stickiness of the photopolymerizationcomposition (e.g., manufacturing failure resulting from the transfer andadhesion of the photosensitive material components), and precipitationfrom a developing solution. The addition polymerizable compound may beused alone or in combination of two or more. In addition, appropriatestructure, compounding ratio and addition amount of the additionpolymerizable compound can be arbitrarily selected taking intoconsideration the degree of polymerization hindrance due to oxygen,resolving power, fogging characteristic, refractive index variation andsurface adhesion. Further, the layer constitution and the coating methodof undercoating and overcoating can be performed according tocircumstances.

Organic polymeric binders which can form a part of the film formingcomponent of the photopatternable layer include: (1) polyesters,including those based on terephthalic, isophthalic, sebacic, adipic, andhexahydroterephthalic acids; (2) nylons or polyamides; (3) celluloseethers and esters; (4) polyaldehydes; (5) high molecular weight ethyleneoxide polymers—e.g., poly(ethylene glycols), having average weightaverage molecular weights from 4000 to 4,000,000; (6) polyurethanes; (7)polycarbonates; (8) synthetic rubbers—e.g., homopolymers and copolymersof butadienes; and (9) homopolymers and copolymers formed from monomerscontaining ethylenic unsaturation such as polymerized forms of any ofthe various ethylenically unsaturated monomers, such aspolyalkylenes—e.g. polyethylene and polypropylene; poly(vinyl alcohol);polystyrene; poly(acrylic and methacrylic acids and esters)—e.g.poly(methyl methacrylate) and poly(ethyl acrylate), as well as copolymervariants. The polymerizable compound and the polymeric binder can beemployed together in widely varying proportions, including polymerizablecompound ranging from 3-97 percent by weight of the film formingcomponent and polymeric binder ranging from 97-3 percent by weight ofthe film forming component. A separate polymeric binder, althoughpreferred, is not an essential part of the photopatternable film and ismost commonly omitted when the polymerizable compound is itself apolymer.

Various photoinitiators can be selected for use in the above-describedimaging systems. Preferred photoinitators consist of an organic dye.

The amount of organic dye to be used is preferably in the range of from0.1 to 5% by weight based on the total weight of the photopolymerizationcomposition, preferably from 0.2 to 3% by weight.

The organic dyes for use as photoinitiators in the present invention maybe suitably selected from conventionally known compounds having amaximum absorption wavelength falling within a range of 300 to 1000 nm.High sensitivity can be achieved by selecting a desired dye having anabsorption spectrum that overlaps with the absorption spectrum of thecorresponding color absorbing material of the multicolor mask describedabove and, optionally, adjusting the absorption spectrum to match thelight source to be used. Also, it is possible to suitably select a lightsource such as blue, green, or red, or infrared LED (light emittingdiode), solid state laser, OLED (organic light emitting diode) or laser,or the like for use in image-wise exposure to light.

Specific examples of the photoinitiator organic dyes include3-ketocoumarin compounds, thiopyrylium salts, naphthothiazolemerocyaninecompounds, merocyanine compounds, and merocyanine dyes containingthiobarbituric acid, hemioxanole dyes, and cyanine, hemicyanine, andmerocyanine dyes having indolenine nuclei. Other examples of the organicdyes include the dyes described in Chemistry of Functional Dyes (1981,CMC Publishing Co., Ltd., pp. 393-416) and Coloring Materials (60 [4],212-224, 1987). Specific examples of these organic dyes include cationicmethine dyes, cationic carbonium dyes, cationic quinoimine dyes,cationic indoline dyes, and cationic styryl dyes. Examples of theabove-mentioned dyes include keto dyes such as coumarin dyes (includingketocoumarin and sulfonocoumarin), merostyryl dyes, oxonol dyes, andhemioxonol dyes; nonketo dyes such as nonketopolymethine dyes,triarylmethane dyes, xanthene dyes, anthracene dyes, rhodamine dyes,acridine dyes, aniline dyes, and azo dyes; nonketopolymethine dyes suchas azomethine dyes, cyanine dyes, carbocyanine dyes, dicarbocyaninedyes, tricarbocyanine dyes, hemicyanine dyes, and styryl dyes;quinoneimine dyes such as azine dyes, oxazine dyes, thiazine dyes,quinoline dyes, and thiazole dyes.

Preferably, the photoinitiator organic dye is a cationic dye-borateanion complex formed from a cationic dye and an anionic organic borate.The cationic dye absorbs light having a maximum absorption wavelengthfalling within a range from 300 to 1000 nm and the anionic borate hasfour R groups, of which three R groups each represents an aryl groupwhich may have a substitute, and one R group is an alkyl group, or asubstituted alkyl group. Such cationic dye-borate anion complexes havebeen disclosed in U.S. Pat. Nos.: 5,112,752; 5,100,755; 5,057,393;4,865,942; 4,842,980; 4,800,149; 4,772,530; and 4,772,541, which areincorporated herein by reference.

When the cationic dye-borate anion complex is used as the organic dye inthe photopolymerization compositions of the invention, it does notrequire to use the organoborate salt. However, to increase thephotopolymerization sensitivity, it is preferred to use an organoboratesalt in combination with the cationic dye-borate complex. The organicdye can be used singly or in combination.

Specific examples of the above-mentioned cationic dye-borate salts aregiven below. However, it should be noted that the present invention isnot limited to these examples.

It may be preferable to use the photoinitiator in combination with anorganic borate salt such as disclosed in U.S. Pat. Nos.: 5,112,752;5,100,755; 5,057,393; 4,865,942; 4,842,980; 4,800,149; 4,772,530; and4,772,541. If used, the amount of borate compound contained in thephotopolymerization composition of the invention is preferably from 0%to 20% by weight based on the total amount of photopolymerizationcomposition. The borate salt useful for the photosensitive compositionof the present invention is represented by the following general formula(I).

[BR₄]⁻Z⁺

where Z represents a group capable of forming cation and is not lightsensitive, and [BR4]⁻is a borate compound having four R groups which areselected from an alkyl group, a substituted alkyl group, an aryl group,a substituted aryl group, an aralkyl group, a substituted aralkyl group,an alkaryl group, a substituted alkaryl group, an alkenyl group, asubstituted alkenyl group, an alkynyl group, a substituted alkynylgroup, an alicyclic group, a substituted alicyclic group, a heterocyclicgroup, a substituted heterocyclic group, and a derivative thereof.Plural R groups may be the same as or different from each other. Inaddition, two or more of these groups may join together directly or viaa substituent and form a boron-containing heterocycle. Z+ does notabsorb light and represents an alkali metal, quaternary ammonium,pyridinium, quinolinium, diazonium, morpholinium, tetrazolium,acridinium, phosphonium, sulfonium, oxosulfonium, iodonium, S, P, Cu,Ag, Hg, Pd, Fe, Co, Sn, Mo, Cr, Ni, As, or Se.

Specific examples of the above-mentioned borate salts are given below.However, it should be noted that the present invention is not limited tothese examples.

Various additives can be used together with the photoinitiator system toaffect the polymerization rate. For example, a reducing agent such as anoxygen scavenger or a chain-transfer aid of an active hydrogen donor, orother compound can be used to accelerate the polymerization. An oxygenscavenger is also known as an autoxidizer and is capable of consumingoxygen in a free radical chain process. Examples of useful autoxidizersare N,N-dialkylanilines. Examples of preferred N,N-dialkylanilines aredialkylanilines substituted in one or more of the ortho-, meta-, orpara-position by the following groups: methyl, ethyl, isopropyl,t-butyl, 3,4-tetramethylene, phenyl, trifluoromethyl, acetyl,ethoxycarbonyl, carboxy, carboxylate, trimethylsilymethyl,trimethylsilyl, triethylsilyl, trimethylgermanyl, triethylgermanyl,trimethylstannyl, triethylstannyl, n-butoxy, n-pentyloxy, phenoxy,hydroxy, acetyl-oxy, methylthio, ethylthio, isopropylthio, thio-(mercapto-), acetylthio, fluoro, chloro, bromo and iodo. Representativeexamples of N,N-dialkylanilines useful in the present invention are4-cyano-N,N-dimethylaniline, 4-acetyl-N,N-dimethylaniline,4-bromo-N,N-dimethylaniline, ethyl 4-(N,N-dimethylamino)benzoate,3-chloro-N,N-dimethylaniline, 4-chloro-N,N-dimethylaniline,3-ethoxy-N,N-dimethylaniline, 4-fluoro-N,N-dimethylaniline,4-methyl-N,N-dimethylaniline, 4-ethoxy-N,N-dimethylaniline,N,N-dimethylaniline, N,N-dimethylthioanicidine4-amino-N,N-dimethylaniline, 3-hydroxy-N,N-dimethylaniline,N,N,N′,N′-tetramethyl-1,4-dianiline, 4-acetamido-N,N-dimethylaniline,2,6-diisopropyl-N,N-dimethylaniline (DIDMA),2,6-diethyl-N,N-dimethylaniline, N,N, 2,4,6-pentamethylaniline (PMA) andp-t-butyl-N,N-dimethylaniline.

It may be preferable to use the photoinitiator in combination with adisulfide coinitiator. Examples of useful disulfides are described inU.S. Pat. No. 5,230,982 by Davis et al. which is incorporated herein byreference. Two of the most preferred disulfides aremercaptobenzothiazo-2-yl disulfide and 6-ethoxymercaptobenzothiazol-2-yldisulfide. In addition, thiols, thioketones, trihalomethyl compounds,lophine dimer compounds, iodonium salts, sulfonium salts, azinium salts,organic peroxides, and azides, are examples of compounds useful aspolymerization accelerators.

Other additives which can be incorporated into the photopatternablecoatings include polymeric binders, fillers, pigments, surfactants,adhesion modifiers, and the like. To facilitate coating on the supportand functional layers the photopatternable film composition is usuallydispersed in a solvent to create a solution or slurry, and then theliquid is evaporatively removed, usually with heating, after coating.Any solvent can be employed for this purpose which is inert toward thefilm forming components and addenda of the photopatternable film.

It may be preferable to practice the invention with positive-workingphotopatternable materials. By way of example, U.S. Pat. No. 4,708,925by Newman (hereby incorporated by reference) describes apositive-working photopatternable composition containing novolakphenolic resins, an onium salt, and a dye sensitizer. In this system,there is an interaction between alkali-soluble phenolic resins and oniumsalts which results in an alkali solvent resistance when it is cast intoa film. Photolytic decomposition of the onium salt restores solubilityto the resin. Unlike the quinine diazides which can only be poorlysensitized, if at all, onium salts can be readily sensitized to a widerange of the electromagnetic spectrum from UV to infrared (280 to 1100nm).

Examples of compounds which are known to sensitize onium salts are thosein the following classes: diphenylmethane including substituteddiphenylmethane, xanthene, acridine, methine and polymethine (includingoxonol, cyanine, and merocyanine) dye, thiazole, thiazine, azine,aminoketone, porphyrin, colored aromatic polycyclic hydrocarbon,p-substituted aminostyryl compound, aminotriazyl methane, polyarylene,polyarylpolyene, 2,5-diphenylisobenzofuran, 2,5-diarylcyclopentadiene,diarylfuran, diarylthiofuran, diarylpyrrole, polyaryl-phenylene,coumarin and polyaryl-2-pyrazoline. The addition of a sensitizer to thesystem renders it sensitive to any radiation falling within theabsorption spectrum of the said sensitizer. Other positive-workingsystems are known to those skilled in the art.

Once a photopatternable layer is exposed, it can be developed by anymeans known the art. Development is the process by which the solubleportions of the photopatternable layer are removed. Methods fordeveloping typically include exposure to a selective solvent, heating,or combinations thereof. A liquid developer can be any convenient liquidwhich is capable of selectively removing the photopatternable layerbased on exposure level. The exposed photopatternable layer can besprayed, flushed, swabbed, soaked, sonicated, or otherwise treated toachieve selective removal. In its simplest form the liquid developer canbe the same liquid employed as a solvent in coating the photopatternablefilm. In some instances the photoresist is not rendered soluble where itis ultimately to be removed, but is instead rendered susceptible to aparticular reaction that occurs during exposure to a developmentsolution which then permits solubility.

In patterning processes where the photopatterned film is not intended tobe part of the final article, it needs to be removed after it has beenused to successfully pattern an area. This removal can be accomplishedwith any means known in the art, included plasma treatments, especiallyplasmas including oxygen, solvent based stripping, and mechanical oradhesive means.

In many embodiments the photopatternable layer is simply a layer used topattern another functional layer. However, circumstances may exist inwhich the photopatterned layer is also the functional layer. Examples ofthis are the use of a photopatternable as a dielectric due to itsinsulating behavior, or as a structural element such as a small wall ormicrocell due to its mechanical properties. This use of photopatternedlayers as functional layers is not limited to the above examples.

In the process for the article of this invention there is required alight source that emits light of some spectrum, the multicolor mask thatcontains at least two color records in which each is capable ofabsorbing light of some spectrum, and a photopatternable layer that iscapable of responding to light of some spectrum.

The system can function in several modes:

(1) White light, defined as light of a very broad visible spectrum, canbe used as the illumination source. In this case, it is required thatthe photopatternable layer have a sensitivity distribution thatsubstantially matches the absorption spectrum of the target color recordof the color mask. Substantially matching spectrum is defined as theintegrated product of the two spectra, each normalized to an area of 1,exceeding 0.5, preferably exceeding 0.75, most preferably exceeding 0.9.

(2) Colored light, as defined by light of a narrow spectrum, can be usedas the illumination source. In this case, the absorption spectrum ofphotopatternable layer can be made to substantially match the spectrumof the emitted light, or the absorption spectrum can be broad. Theformer case may be desirable for improved sensitivity of thephotopatternable layer and reduced cross talk between layers, while thelatter case may be desirable for allowing several process steps toemploy a single photopatternable layer formulation.

In some cases it may be desirable to apply a black layer to part of themulticolor mask. Such a black layer has the property of absorbingsubstantially all of the light in those areas of the mask having theblack layer. If, for example, large areas of the final product aredesired to have no patterning, a black printed mask can be used in thoseareas.

In much of the preceding discussion the color mask is referred to ashaving color absorption corresponding to the traditional observablecolors of the visible spectrum. However, this applies a limitation tothe number of individual mask levels that can be accomplished with thisapproach. In principle a high number of individual color records can beused provided that each color record can be independently addressed inthe process. In addition, by utilizing infrared and ultraviolet portionsof the spectrum, the number of mask levels may further be increased. Itis envisioned that upwards of 6 individual mask levels can be achievedwith the current invention.

In this process, light passes through the multicolor mask and thenthrough the previously applied functional layers on the front of thesubstrate. As a result, the light must pass through the previouslyapplied layers with weak enough modulation as to not overly affect theresulting images formed on the applied light curable layers. Therequirement for transparency of the applied functional layers is thuslimited to having an acceptably low effect on the curable layer imagingprocess. In principle therefore, the previously applied can absorb lightuniformly as long as this absorption is low, preferably having anoptical density of less than 0.5. Furthermore, the materials can absorbvery strongly but only in regions where the imaging chemistry is notbeing used, or where these spectral ranges have been used but in priorstages of the manufacture of the article. Furthermore, the final layerin the process can be of any opacity, since additional patterning is notrequired on top.

An aspect of this invention is the ability to at will use one of thecolors of the multicolor mask to form a pattern on the front side of theitem by the direction light through the substrate to cause an effect. Anumber of methods can be used to cause the patterning.

(a) A functional material can be coated uniformly over the multicolormask of the item and then overcoated with a photopatternable resistmaterial that hardens when it is exposed to light through the substrate.The hardened material is then more difficult to remove, so in asubsequent development step, the photopatternable resist is patterned tohave openings where no light has struck. The item can then be exposed toa material that attacks the functional layer, thus removing it where nolight has struck. This is a negative etch process.

(b) A functional material can be coated uniformly upon over themulticolor mask of the item and then overcoated with a photopatternableresist material that softens when it is exposed to light from the backside. The softened materials is then easier to remove, so in asubsequent development step, the resist is patterned to have openingswhere light has struck. The item can then be exposed to a material thatattacks the functional layer, thus removing it where light has struck.This is a positive etch process.

(c) A photopatternable resist material can be coated followed byexposure and development step as outlined in (a) or (b). This will yielda resist pattern that has holes in it. This can then be overcoated witha uniform layer of a functional material. If the entire item is thentreated with a material that attacks the remaining photoresist under thefunctional material, it can remove material where photoresist resides.This will leave functional material where there was originally nophotoresist.

(d) A number of deposition processes employing both liquids and vaporphase chemical delivery can be tailored to operate in a manner wherematerial selectively deposits only in certain areas. For example, aphotopatternable resist material can be coated followed by exposure anddevelopment step as outlined in (a) or (b). Next, a deposition processthat leads to material being deposited only in those regions where noresist material remains. The entire item is then treated with a materialthat attacks the remaining resist. This is selective deposition.

A support can be used for supporting the device during manufacturing,testing, and/or use. As used in this disclosure, the terms “support” and“substrate” may be used interchangeably. The skilled artisan willappreciate that a support selected for commercial embodiments may bedifferent from one selected for testing or screening variousembodiments. In some embodiments, the support does not provide anynecessary electrical function for the device. This type of support istermed a “non-participating support” in this document. Useful materialscan include organic or inorganic materials. For example, the support maycomprise inorganic glasses, ceramic foils, polymeric materials, filledpolymeric materials, acrylics, epoxies, polyamides, polycarbonates,polyimides, polyketones,poly(oxy-1,4-phenyleneoxy-1,4-phenylenecarbonyl-1,4-phenylene)(sometimes referred to as poly(ether ether ketone) or PEEK),polynorbomenes, polyphenyleneoxides, poly(ethylenenaphthalenedicarboxylate) (PEN), poly(ethylene terephthalate) (PET),poly(ether sulfone) (PES), poly(phenylene sulfide) (PPS), andfiber-reinforced plastics (FRP).

A flexible support is used in some embodiments. This allows forroll-to-roll or roll-to-sheet processing, which may be continuous,providing economy of scale and economy of manufacturing over flat and/orrigid supports. The flexible support chosen preferably is capable ofwrapping around the circumference of a cylinder of less than about 50 cmdiameter, more preferably 25 cm diameter, most preferably 10 cmdiameter, without distorting or breaking, using low force as by unaidedhands. The preferred flexible support may be rolled upon itself.

If flexibility is not a concern, then the substrate may be a wafer orsheet made of materials including glass as well as any other transparentmaterial.

The thickness of the substrate may vary, and according to particularexamples it can range from about 10 μm to about 1 mm. Preferably, thethickness of the substrate is in the range from about 10 μm to about 300μm. Provided the exposing light source is sufficiently collimated tolimit the angular spread of light through the support layer, eventhicker substrates can be tolerated. Particularly for embodiments wherea portion of the multicolor mask is on the back side of the support itmay be advantageous, for optical considerations, to coat or cast themain support layer directly onto the color absorbing layers of thesecond portion of the multicolor mask. In some embodiments, the supportis optional, particularly when support layer is a functional layer or acolor absorbing layer of the multicolor mask.

In addition, the multicolor mask and support may be combined with atemporary support. In such an embodiment, a support may be detachablyadhered or mechanically affixed to the multicolor mask.

Any material that can form a film on the substrate can be patterned withthis invention, as long as the appropriate etching and or depositionconditions are chosen. Functional materials typically have aninter-related useful function in an electronic component of anelectronic device or in electric circuitry. General classes offunctional materials that can be used include conductors, dielectrics orinsulators, and semiconductors. Functional materials of the presentinvention may be deposited in using any convenient method. Typicaldeposition processes include chemical vapor deposition, sputtering,evaporation, thermal transfer or solution processing. One embodiment ofthe current invention, the functional materials are applied usinggravure or inkjet. In another embodiment the functional material isdeposited using Atomic Layer Deposition (ALD). In a preferred embodimentof the present invention, the functional material is deposited by an ALDsystem consisting of a gas distribution manifold having a plurality ofopenings through which first and second reactive gases flow as themanifold and the substrate move relative to each other. Co-pending,commonly assigned U.S. Ser. No. 11/392,007, filed Mar. 29, 2006,describes such a method in detail and the disclosure of which is herebyincorporated in its entirety by reference.

Conductors can be any useful conductive material. A variety of conductormaterials known in the art, are also suitable, including metals,degenerately doped semiconductors, conducting polymers, and printablematerials such as carbon ink, silver-epoxy, or sinterable metalnanoparticle suspensions. For example, the conductor may comprise dopedsilicon, or a metal, such as aluminum, chromium, gold, silver, nickel,copper, tungsten, palladium, platinum, tantalum, and titanium.Conductors can also include transparent conductors such as indium-tinoxide (ITO), ZnO, SnO₂, or In₂O₃. Conductive polymers also can be used,for example polyaniline, poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT:PSS). In addition, alloys, combinations, andmultilayers of these materials may be most useful.

The thickness of the conductor may vary, and according to particularexamples it can range from about 5 to about 1000 nm. The conductor maybe introduced into the structure by chemical vapor deposition,sputtering, evaporation and/or doping, or solution processing.

A dielectric electrically insulates various portions of a patternedcircuit. A dielectric layer may also be referred to as an insulator orinsulating layer. The dielectric should have a suitable dielectricconstant that can vary widely depending on the particular device andcircumstance of use. For example, a dielectric constant from about 2 to100 or even higher is known for a gate dielectric. Useful materials fora dielectric may comprise, for example, an inorganic electricallyinsulating material. Specific examples of materials useful for the gatedielectric include strontiates, tantalates, titanates, zirconates,aluminum oxides, silicon oxides, tantalum oxides, titanium oxides,silicon nitrides, barium titanate, barium strontium titanate, bariumzirconate titanate, zinc selenide, and zinc sulfide. In addition,alloys, combinations, and multilayers of these examples can be used as adielectric. Of these materials, aluminum oxides, silicon oxides, andsilicon nitride are useful. The dielectric may comprise a polymericmaterial, such as polyvinylidenedifluoride (PVDF), cyanocelluloses,polyimides, polyvinyl alcohol, poly(4-vinylphenol), polystyrene andsubstituted derivatives thereof, poly(vinyl naphthalene) and substitutedderivatives, and poly(methyl methacrylate) and other insulators having asuitable dielectric constant. The gate electric may comprise a pluralityof layers of different materials having different dielectric constants.

The thickness of a dielectric layer may vary, and according toparticular examples it can range from about 15 to about 1000 nm. Thedielectric layer may be introduced into the structure by techniques suchas chemical vapor deposition, sputtering, atomic layer deposition,evaporation, or a solution process.

Semiconductors used in this system may be organic or inorganic.Inorganic semiconductors include classes of materials exhibitingcovalently bonded lattices, and may also include amorphous materialswhere the lattice exhibits only short range order. Examples of usefulsemiconducting materials are single elements such as silicon orgermanium, and compound semiconductors such as gallium arsenide, galliumnitride, cadmium sulfide, and zinc oxide. Useful organic semiconductorsinclude linear acenes such as pentacenes, naphthalenediimides such asthose described in co-pending patent applications, perylenediimides,polythiophenes, polyfluorenes.

In typical applications of a thin film transistor, the desire is for aswitch that can control the flow of current through the device. As such,it is desired that when the switch is turned on a high current can flowthrough the device. The extent of current flow is related to thesemiconductor charge carrier mobility. When the device is turned off, itis desired that the current flow be very small. This is related to thecharge carrier concentration. Furthermore, it is desired that the devicebe weakly or not at all influenced by visible light. In order for thisto be true, the semiconductor band gap must be sufficiently large (>3eV) so that exposure to visible light does not cause an inter-bandtransition. A material that is capable of yielding a high mobility, lowcarrier concentration, and high band gap is ZnO.

The entire process of making the thin film transistor or electronicdevice of the present invention, or at least the production of the thinfilm semiconductor, is preferably carried out below a maximum supporttemperature of about 200° C., more preferably below 150° C., mostpreferably below about 140° C., and even more preferably below about100° C., or even at temperatures around room temperature (about 25° C.to 70° C.). The temperature selection generally depends on the supportand processing parameters known in the art, once one is armed with theknowledge of the present invention contained herein. These temperaturesare well below traditional integrated circuit and semiconductorprocessing temperatures, which enables the use of any of a variety ofrelatively inexpensive supports, such as flexible polymeric supports andthe multicolor mask. Thus, the invention enables production ofrelatively inexpensive circuits containing thin film transistors.

Electronically or optically active layers may be formed and doped usingsolution processes, vacuum vapor deposition techniques, or atmosphericvapor deposition processes such as those described in co-pending PatentPublication Nos. 2007/0228470 and 2007/0238311, both filed Mar. 29,2006.

The patterning methods of this invention are preferably used to createelectrically and optically active components that are integrated on asubstrate of choice. Circuit components can comprise transistors,resistors, capacitors, conductors, inductors, diodes, and any otherelectronics components that can be constructed by selecting theappropriate patterning and materials. Optically functional componentscan comprise waveguides, lenses, splitters, diffusers, brightnessenhancing films, and other optical circuitry. Structural components cancomprise wells, selective patterns of fillers and sealants, patternedbarrier layers, walls and spacers.

Electronic devices in which TFTs and other devices are useful include,for example, more complex circuits, e.g., shift registers, integratedcircuits, logic circuits, smart cards, memory devices, radio-frequencyidentification tags, backplanes for active matrix displays,active-matrix displays (e.g. liquid crystal or OLED), solar cells, ringoscillators, and complementary circuits, such as inverter circuits, forexample, in which a combination of n-type and p-type transistors areused. In an active matrix displays, a transistor made according to thepresent invention can be used as part of voltage hold circuitry of apixel of the display. In such devices, the TFTs are operativelyconnected by means known in the art.

One example of a microelectronic device is an active-matrixliquid-crystal display (AMLCD). One such device is an optoelectronicdisplay that includes elements having electrodes and an electro-opticalmaterial disposed between the electrodes. A connection electrode of thetransparent transistor may be connected to an electrode of the displayelement, while the switching element and the display element overlap oneanother at least partly. An optoelectronic display element is hereunderstood to be a display element whose optical properties change underthe influence of an electrical quantity such as current or voltage suchas, for example, an element usually referred to as liquid crystaldisplay (LCD). The presently detailed transistor has sufficient currentcarrying capacity for switching the display element at such a highfrequency that the use of the transistor as a switching element in aliquid crystal display is possible. The display element acts inelectrical terms as a capacitor that is charged or discharged by theaccompanying transistor. The optoelectronic display device may includemany display elements each with its own transistor, for example,arranged in a matrix. Certain active matrix pixel designs, especiallythose supplying a display effect that is current driven, may requireseveral transistors and other electrical components in the pixelcircuit.

The following non-limiting examples further describe the practice of theinstant invention.

EXAMPLES A. Visible Light Curable Film Components

The following materials and coating solutions were used to prepare thevisible light curable films. Stock solution CF-1 contained two grams ofpolymethylmethacrylate (PMMA) (MW˜75K), 6.5 g of trimethylolpropanetriacrylate, and 20 g of anisole. Stock solution CF-2 contained 1.5grams of ethoxylated trimethylolpropane triacrylate (SR9035 purchasedfrom Sartomer Company, Inc.) and 1.5 g of polyethylene glycol diacrylate(SR610 purchased from Sartomer Company, Inc.) in 4 g of ethanol. Stocksolution CF-3 was a commercial resist CT2000L supplied by FujiPhotochemicals containing a methacrylate derivative copolymer andpolyfunctional acrylate resin in a mixture of2-propanol-1-methoxyacetate and 1-ethoxy-2-propanol acetate. Stocksolution CF-4 contained 1.25 g of a Novolak resin, and 0.2 g of Irgacure250 (purchased from CIBA Specialty Chemicals), in MEK. Stock solutionCF-5 was a positive-working commercial resist SC-1827, (purchased fromRohm and Haas Electronic Materials). Stock solution CF-6 was prepared asfollows. DEHESIVE 944 is a vinyl-terminated dimethylsiloxane polymersupplied by Wacker Chemie AG. Crosslinker V24 is amethylhydrogenpolysiloxane supplied by Wacker. Catalyst OL is anorganoplatinum complex in polydimethylsiloxane, also supplied by Wacker.Crosslinker V24 and Catalyst OL are used for additional curing ofvinyl-terminated siloxane polymers such as DEHESIVE 944. A solution wasprepared which contained 3.3 g of a 1% solution ofpolymethylmethacrylate dissolved in toluene, 0.5 g of a 10% solution ofTMPTA in toluene, 0.25 g of a 0.1% solution of Photoinitiator A inanisole, 0.5 g of a solution containing 1.08% DEHESIVE 944, 0.002%Crosslinker V24, and 0.06% Catalyst OL in a mixture of 33 parts tolueneand 48 parts heptane, and 0.85 g of toluene. One gram of the resultingsolution was diluted with 5 g of toluene to prepare stock solution CF-6.

The stock solutions CF1-CF4 were sensitized to visible light by additionof a dye photoinitiator. Photoinitiator structures appear in Table 1.Photoinitiator solutions were prepared as follows. YPI-1 was a 1%solution of yellow photoinitiator A in anisole. YPI-2 was a 1% solutionof yellow photoinitator A in ethanol. YPI-3 was a 1% solution of yellowphotoinitiator A in cyclohexanone. MPI-1 was a 1% solution of magentaphotoinitiator B in anisole. MPI-2 was a 1% solution of magentaphotoinitiator B in ethanol. MPI-3 was a 1% solution of magentaphotoinitiator in cyclohexanone. CPI-1 was a 1% solution of cyanphotoinitiator C in anisole. CPI-2 was a 1% solution of photoinitiator Cin ethanol. CPI-3 was a 1% solution of photoinitiator C incyclohexanone.

Developer solution D-1 was MIBK. Developer solution D-2 was ethanol.Developer solution D-3 was an aqueous solution containing 0.002 Mtetramethylammonium hydroxide and 0.002 M diethanolamine. Developersolution D-4 was Kodak Goldstar Plus Positive Plate Developer. Developersolution D-5 was Microposit™ MF™-319, purchased from Rohm and HaasElectronic Materials

TABLE 1 Dye λmax Photoinitiator A

450 nm Photoinitiator B

555 nm Photoinitiator C

645 nmB. Electronic materials deposition and patterning

The following materials and methods were used to deposit electronicmaterials. Alumina coatings were of type A-1 were applied using a CVDprocess with trimethylaluminum and water as reactive materials entrainedin a nitrogen carrier gas. Zinc oxide coatings of type ZnO-1 wereapplied using a CVD process with diethyl zinc and water as reactivematerials entrained in a nitrogen carrier gas. The device used toprepare the Al₂O₃ layers of type A-2 and A-3 and ZnO layers of typeZnO-2 has been described in detail in U.S. patent application Ser. No.11/627,525, hereby incorporated by reference in its entirety. Aluminacoatings of type A-2 were applied using this coating device withtrimethylaluminum and water as reactive materials entrained in anitrogen carrier gas. Alumina coatings of type A-3 were applied usingthis coating device with dimethylaluminum isopropoxide (DMAI) and wateras reactive materials. Zinc oxide coatings of type ZnO-2 were appliedusing this ALD coating device with diethyl zinc and water as reactivematerials entrained in a nitrogen carrier gas. Indium tin oxide (ITO)coatings were applied using a sputter coater. Aluminum coatings (Al)were evaporated.

The following solutions were used to etch the functional materials. E-1was a 50/50 mixture of HCl and water. E-2 was Kodak Ektacolor RA-4bleach-fix solution. E-3 was a 0.25 molar solution of acetic acid inwater. E-4 was Microposit™ MF™-319 Developer purchased from Rohm andHaas Electronic Materials. Subbing layer S-1 was a 7.5% solution ofpolycyanoacrylate in a 50/50 mixture of acetonitrile and cyclopentanone.S-2 was Omnicoat™, purchased from MicroChem.

Example 1 Multicolor Mask Formed by Direct Printing Process

In this example, a multicolor mask MM-1 was prepared containing 3 colorabsorbing layers, with each color corresponding to an individualfunctional layer of an array of thin film transistor devices. A colorimage was created using Photoshop 6.0. In this image, the blue channelcontained the gate layer design as a blue color absorber pattern BCA-1.The green channel contained the semiconductor layer design as a greencolor absorber pattern GCA-1. The red channel contained the source anddrain design as a red color absorber pattern RCA-1. This color image wasprinted onto a transparent support using a Kodak Professional 8670Thermal Printer loaded with Kodak Professional Ektatherm XLStransparency media. The Optical Density (Status M) to red light (cyanOD), green (magenta OD), and blue light (yellow OD) and peak wavelengthof the individual color absorbing layers in MM-1 is shown in Table 2below.

TABLE 2 Optical Density (Status M) Cyan OD Magenta (OD) Yellow (OD) λmaxBCA-1 0.02 0.08 1.38 460 nm GCA-1 0.08 1.44 0.38 548 nm RCA-1 1.73 0.290.09 683 nm

Example 2 Multicolor Mask Formed by Photolithography Process

In this example, a multicolor mask MM-2 was prepared containing 3 colorabsorbing layers RCA-2, GCA-2, and BCA-2 and planarizing layer P-2, witheach color corresponding to an individual functional layer of an arrayof thin film transistor devices. Cyan (SC3200L), magenta (SM3000L),yellow (SY3000L), and clear (CT-2000L) UV curable photoresists werepurchased from Fujifilm Electronic Materials Co., Ltd. Laser-writtenmolybdenum on glass masks were prepared for the gate layer (CG-1),semiconductor and dielectric layers (CG-2), and source and drain layers(CG-3) of the array of thin film transistor devices. Photoresistcoatings were aligned and exposed to UV light using a contact alignerequipped with a 200W Mercury-Xenon lamp. Red color absorbing layer RCA-2was applied to a clean glass support by the following method. The glasssubstrate was spin coated (at 1000 RPM) with the cyan photoresistSC3200L, baked for 1 minute at 95° C., and exposed using mask CG-1. Thecoating was developed, and baked for 5 minutes at 200° C., forming redcolor absorbing layer RCA-2. The sample was then spin coated (at 1000RPM) the magenta photoresist SM3000L, baked for 1 minute at 95° C., andexposed using mask CG-3. The coating was developed, and baked for 5minutes at 200° C. forming green color absorbing layer GCA-2. The samplewas then spin coated (at 1000 RPM) with yellow photoresist, SY3000L,baked for 1 minute at 95° C., and exposed using mask CG-2 (contactexposure). The yellow photoresist layer was developed, and baked for 5minutes at 200° C. forming blue color absorbing layer BCA-2. The samplewas then spin coated (at 1000 RPM) with clear photoresist CT2000L,exposed to UV light and baked for 5 minutes at 200° C. The resultingmulticolor mask MM-2 contained an array of registered cyan (RCA-2),magenta (GCA-2), and yellow (BCA-2) patterns and a clear planarizinglayer P-2. The Optical Density (Status M) to red light (cyan OD), green(magenta OD), and blue light (yellow OD) and peak wavelength of theindividual color absorbing layers in MM-2 is shown in Table 3 below.

TABLE 3 Optical Density (Status M) Cyan OD Magenta (OD) Yellow (OD) λmaxBCA-2 0.03 0.05 0.97 465 nm GCA-2 0.05 1.02 0.18 565 nm RCA-2 0.94 0.130.05 625 nm

Example 3 Photographic Replication of a Master Color Image

This example illustrates the replication of a master color mask using afull color, high resolution, silver halide film to form multicolor masksMM-3. A multicolor mask was prepared in the same manner as described inExample 2. Twenty copies of the multicolor mask were prepared by contactprinting to Eastman Color Print™ film using a photographic enlarger. Theexposed photographic negatives were developed, fixed, and washed. Eachresulting multicolor mask MM-3 contained an array of registered cyan,magenta, and yellow patterns.

Example C4-C6

In this set of examples, multicolor mask MM-1 is used in combinationwith blue-sensitive coating C-4, green-sensitive coating C-5, andred-sensitive coating C-6, to produce distinct photopatterns. Becausethe colorants in the multicolor mask are spectrally distinct, thepatterns encoded in the multicolor masks are addressed simply bychanging the dye photoinitiator and color of exposing light.

Photosensitive coatings were prepared from a solution that contained 3.9g of CF-1 and 0.5 g of the photoinitiator solution indicated in Table 4.The coatings were prepared by spin coating at 1000 RPM for one minuteand were dried for one minute at 80° C. and loaded in a glass cellpurged with nitrogen. The peak wavelength of the resultingphotosensitive coatings, λmax, is shown in Table 4. The coatings wereilluminated with colored light in such fashion that exposing lightpassed through the glass support and multicolor mask MM-1 beforereaching the photosensitive coating. Unexposed portions of thephotosensitive coating were removed by developing for 1 minute in D-1.These steps resulted in formation of a negative patterned polymer filmcorresponding to a specific a color pattern on the multicolor mask.Results are summarized in Table 4 below. In example C-4, thephotopattern produced corresponded to the blue color absorber patternBCA-1, establishing that this coating formulation is a negative-working,blue sensitive film. In example C-5, the photopattern producedcorresponded to the green color absorber pattern GCA-1, establishingthat this coating is a negative-working, green sensitive film. Inexample C-6, the photopattern produced corresponded to the red colorabsorber pattern RCA-1, establishing that this formulation is anegative-working, red sensitive film.

TABLE 4 Stock Photo- Exposing Photopattern Example Solution initiatorλmax light obtained C-4 CF-1 YPI-1 450 nm Blue BCA-1/negative C-5 CF-1MPI-1 557 nm Green GCA-1/negative C-6 CF-1 CPI-1 656 nm RedRCA-1/negative

Example C7-C9

In this set of examples, multicolor mask MM-2 is used in combinationwith blue-sensitive coating C-7, green-sensitive coating C-8, andred-sensitive coating C-9, to produce distinct photopatterns. Thesephotosensitive coatings are negative-working.

Coating solutions contained 7 g of CF-2 and 0.6 g of the photoinitiatorsolution indicated in Table 5. These solutions were coated, exposed, anddeveloped in the same manner as for examples C4-C6, with the exceptionthat multicolor mask MM-2 was used and the coatings were developed usingdeveloper solution D-2. These steps resulted in formation of a negativepatterned polymer film corresponding to a specific a color pattern onthe multicolor mask. Results are summarized in Table 5 below. In exampleC-7, the photopattern produced corresponded to the blue color absorberpattern BCA-2, establishing that this coating formulation is anegative-working, blue sensitive film. In example C-8, the photopatternproduced corresponded to the green color absorber pattern GCA-2,establishing that this coating is a negative-working, green sensitivefilm. In example C-9, the photopattern produced corresponded to the redcolor absorber pattern RCA-2, establishing that this formulation is anegative-working, red sensitive film.

TABLE 5 Stock Exposing Photopattern Example Solution Photoinitiatorlight obtained C-7 CF-2 YPI-2 Blue BCA-2/negative C-8 CF-2 MPI-2 GreenGCA-2/negative C-9 CF-2 CPI-2 Red RCA-2/negative

Examples C10-C12

In this set of examples, multicolor mask MM-2 is used in combinationwith blue-sensitive coating C-10, green-sensitive coating C-11, andred-sensitive coating C-12, to produce distinct photopatterns. Thesephotosensitive coatings are negative-working.

Coating solutions contained 4 g of CF-3 and 0.5 g of the photoinitiatorsolution indicated in Table 6. The coating solution was spin coated at2000 RPM for one minute and dried for 2 minutes at 90° C. A 10% PVAcoating was applied at 1000 RPM for 2 minutes and dried at 90° C. for 2minutes at 90° C. These coatings were exposed in air and developed inthe same manner as for examples C7-C9, with the exception thatmulticolor mask MM-2 was used and the coatings were developed usingdeveloper solution D-3. These steps resulted in formation of a negativepatterned polymer film corresponding to a specific a color pattern onthe multicolor mask. Results are summarized in Table 6 below. In exampleC-10, the photopattern produced corresponded to the blue color absorberpattern BCA-2, establishing that this coating formulation is anegative-working, blue sensitive film. In example C-11, the photopatternproduced corresponded to the green color absorber pattern GCA-2,establishing that this coating is a negative-working, green sensitivefilm. In example C-12, the photopattern produced corresponded to the redcolor absorber pattern RCA-2, establishing that this formulation is anegative-working, red sensitive film.

TABLE 6 Stock Exposing Photopattern Example Solution Photoinitiatorlight obtained C-10 CF-3 YPI-3 Blue BCA-2/negative C-11 CF-3 MPI-3 GreenGCA-2/negative C-12 CF-3 CPI-3 Red RCA-2/negative

Examples C13-C15

In this set of examples, multicolor mask MM-2 is used in combinationwith blue-sensitive coating C-13, green-sensitive coating C-14, andred-sensitive coating C-15, to produce distinct photopatterns. Thesephotosensitive coatings are positive-working.

Coating solution CF13 contained 5 g of CF-4 and 2 g of the YPI-3.Coating solution CF-14 contained 5 g of CF-4 and 2 g of MPI-3. Thesecoating solutions were spin coated at 2000 RPM for one minute and driedfor 1 minute at 80° C. These coatings were exposed in air and developedin the same manner as for examples C4-C6, with the exception thatmulticolor mask MM-2 was used and the coatings were developed for 20seconds using developer solution D-4. These steps resulted in formationof a positive patterned polymer film corresponding to a specific a colorpattern on the multicolor mask. Results are summarized in Table 7 below.In example C-13, the photopattern produced corresponded to the bluecolor absorber pattern BCA-2, establishing that this coating formulationis a positive-working, blue sensitive film. In example C-14, thephotopattern produced corresponded to the green color absorber patternGCA-2, establishing that this coating is a positive-working, greensensitive film. In example C-15, the photopattern produced correspondedto the red color absorber pattern RCA-2, establishing that thisformulation is a positive-working, red sensitive film. Similarly,coating C-16 was prepared and exposed with blue light, developed usingD-5, forming a positive resist image corresponding to BCA-2.

TABLE 7 Stock Exposing Photopattern Example Solution Photoinitiatorlight obtained C-13 CF-4 YPI-3 Blue BCA-2/positive C-14 CF-4 MPI-3 GreenGCA-2/positive C-16 CF-5 As purchased Blue BCA-2/positive

Example C17-C34 Materials Patterning using Etch Process

In Examples C17-C34, a multicolor mask is used in combination withvisible-light sensitive coatings to pattern transparent electronicmaterials in an etch process. Because the colorants in the multicolormask are spectrally distinct, the patterns encoded in the multicolormasks are addressed simply by changing the dye photoinitiator and colorof exposing light.

Photosensitive coatings were prepared directly on the transparentfunctional material, exposed, and developed according to the proceduresdescribed for Examples C4-C16, as indicated in Table 8. Coatings wereexposed in such fashion that exposing light passed through the supportand multicolor mask before reaching the photosensitive coating. Thefunctional material was patterned by immersing the sample in the etchbath indicated, rinsed, and dried. Results are summarized in Table 8.For Examples C-17 through C-30, a negative-working resist pattern iscombined with an etch step. This sequence of steps results in afunctional material pattern which corresponds to a negative of the colorabsorber pattern. For Examples C31-C35, a positive-working resistpattern is combined with an etch step. This sequence of steps results ina functional material pattern which corresponds to a positive of thecolor absorber pattern. The results in Table 8 further illustrate that asingle multicolor mask may be used to produce a variety of functionalmaterial patterns by varying the sensitivity of the photopatternablematerial.

TABLE 8 Photo- Ex- Functional patternable Exposing Etch Photopatternample Material Formulation light Bath obtained C-17 ITO C-4 Blue E-1BCA-1/negative C-18 ITO C-5 Green E-1 GCA-1/negative C-19 ITO C-6 RedE-1 RCA-1/negative C-20 ITO C-7 Blue E-1 BCA-2/negative C-21 ITO C-11Green E-1 GCA-3/negative C-22 ITO C-12 Red E-1 RCA-2/negative C-23 ITOC-13 Blue E-1 BCA-2/positive C-24 ITO C-16 Blue E-1 BCA-2/positive C-25Ag C-6 Red E-2 RCA-1/negative C-26 ZnO C-4 Blue E-3 BCA-1/negative C-27ZnO C-5 Green E-3 GCA-1/negative C-28 ZnO C-6 Red E-3 RCA-1/negativeC-29 ZnO C-7 Blue E-3 BCA-2/negative C-30 ZnO C-11 Green E-3GCA-2/negative C-31 ZnO C-16 Blue E-3 BCA-2/positive C-32 Al₂O₃ C-13Blue E-4 BCA-2/positive C-33 Al₂O₃ C-16 Blue E-4 BCA-2/positive C-34Al₂O₃ C-16 Blue E-4 BCA-3/positive

Examples C35-C40 Materials Patterning using Liftoff Process

In Examples C35-C40, a multicolor mask is used in combination withvisible-light sensitive coatings to pattern transparent electronicmaterials in a liftoff process. Because the colorants in the multicolormask are spectrally distinct, the patterns encoded in the multicolormasks are addressed simply by changing the dye photoinitiator and colorof exposing light.

A subbing layer was applied to the substrates as indicated in Table 9 toimprove the quality of the patterned layers. Photosensitive coatingswere prepared, exposed, and developed according to the proceduresdescribed for Examples C4-C16, as indicated in Table 9. Coatings wereexposed in such fashion that exposing light passed through the supportand multicolor mask before reaching the photosensitive coating. Thefunctional material was deposited on the substrate after thephotosensitive coating was developed. The photopatterned material wasremoved from the substrate using acetone. Results are summarized inTable 9. For Examples C-35 through C-38, a negative-working resistpattern is combined with an liftoff step. This sequence of steps resultsin a functional material pattern which corresponds to a positive of thecolor absorber pattern. For Examples C38-C39, a positive-working resistpattern is combined with a liftoff step. This sequence of steps resultsin a functional material pattern which corresponds to a negative of thecolor absorber pattern. The results in Table 9 further illustrate that asingle multicolor mask may be used to produce a variety of functionalmaterial patterns by varying the sensitivity of the photopatternablematerial.

TABLE 9 Functional Photopatternable Exposing Liftoff PhotopatternExample Material Formulation light Sub Solvent obtained C-35 Ag C-7 BlueS-1 acetone BCA-1/ positive C-36 Al₂O₃/ZnO C-7 Blue S-1 Acetone BCA-2/stack positive C-37 Al₂O₃ C-7 Blue S-1 Acetone BCA-2/ positive C-38Al₂O₃ C-11 Green Omnicoat Acetone GCA-2/ positive C-39 Al₂O₃ C-16 BlueOmnicoat Acetone BCA-2/ negative

Examples C40-C42 Materials Patterning using Selective Deposition Process

In Examples C40-C42, a multicolor mask is used in combination withvisible-light sensitive coatings to pattern transparent electronicmaterials in a selective deposition process. Because the colorants inthe multicolor mask are spectrally distinct, the patterns encoded in themulticolor masks are addressed simply by changing the dye photoinitiatorand color of exposing light.

Photosensitive coatings were prepared, exposed, and developed accordingto the procedures described for Examples C4-C16, as indicated in Table10. Coatings were exposed in such fashion that exposing light passedthrough the support and multicolor mask before reaching thephotosensitive coating. After the photosensitive coating was developed,the functional material was selectively deposited on regions not maskedby the photopatterned coating. Results are summarized in Table 10. Forexample C40, a layer of silver nanoparticle ink was selectively appliedusing an inkjet printing device, the sample was annealed to form aconducting patterned film. Inkjet printing experiments were performedusing a system consisting of a sample platen supported by a set of X-Ytranslation stages, piezoelectric demand-mode printheads supported by aZ translation stage, and software to control these components. Theprintheads of this inkjet system are suited to dispense droplets in the20-60 picoliter range. Approximately 2 cc of the silver nanoparticle inkwas placed in a sample cartridge which was then screwed to the printingfixture. The printhead was primed with ink using pressurized nitrogen.The sample was placed on the sample holder of the inkjet printingsystem, and the silver nanoparticle ink was selectively applied in thedesired pattern, aligned to the photopatterned film with the aid of atop view camera. Optical micrographs clearly showed the silver patternwas corresponded to the green color absorbing pattern, without“spillage” onto the top surface of the photopatterned coating C-7. Forexample C-41, a 200 Angstrom thick ZnO film of type ZnO-2 wasselectively grown on the photopatterned coating of type C10.Ellipsometry data indicated the ZnO was selectively deposited. Forexample C-42, stock solution CF-6 was spin coated at 2000 RPM, baked at80° C. for one minute, exposed and developed using developer D-1. AnAl₂O₃ layers of type A-3 was selectively deposited. Ellipsometry dataindicated the photosensitive layer inhibited a 500 Angstrom thick layerof alumina.

TABLE 10 Functional Ex- Material Photo- Material am- FunctionalDeposition patternable Exposing pattern ple Material Method Formulationlight obtained C-40 Ag Inkjet C-7 Green GCA-2/positive C-41 ZnO-2 ALDC-10 Blue BCA-2/positive C-42 Al₂O₃-3 ALD CF-6 Blue BCA-2/positive

Example T-43 Thin Film Transistor

In this example, thin film transistors were prepared using a multicolormask to pattern transparent electronic materials. A multicolor mask wasprepared on a glass substrate and a planarizing layer was applied. Thethin film transistors were prepared on the same side of the substrate asthe color mask. Electrical characterization of the fabricated deviceswas performed with a Hewlett Packard HP 4156® parameter analyzer. Devicetesting was done in air in a dark enclosure.

The results were averaged from several devices. For each device, thedrain current (Id) was measured as a function of source-drain voltage(Vd) for various values of gate voltage (Vg). Furthermore, for eachdevice the drain current was measured as a function of gate voltage forvarious values of source-drain voltage. Vg was swept from minus 10 V to40 V for each of the drain voltages measured, typically 5 V, 20 V, and35 V, and 50 V. Mobility measurements were taken from the 35V sweep.

Parameters extracted from the data include field-effect mobility (11),threshold voltage (Vth), subthreshold slope (S), and the ratio ofIon/Ioff for the measured drain current. The field-effect mobility wasextracted in the saturation region, where Vd>Vg−Vth. In this region, thedrain current is given by the equation (see Sze in SemiconductorDevices—Physics and Technology, John Wiley & Sons (1981)):

$I_{d} = {\frac{W}{2L}{{\mu C}_{ox}\left( {V_{g} - V_{th}} \right)}^{2}}$

Where, W and L are the channel width and length, respectively, andC_(ox) is the capacitance of the oxide layer, which is a function ofoxide thickness and dielectric constant of the material. Given thisequation, the saturation field-effect mobility was extracted from astraight-line fit to the linear portion of the √{square root over(I_(d))} versus Vg curve. The threshold voltage, V_(th), is thex-intercept of this straight-line fit.

The first step in fabricating the transistors was to prepare themulticolor mask using the same procedure employed to fabricatemulticolor mask MM-2. In this color mask, the cyan color absorberpattern was a negative of the desired TFT gate pattern. The blue colorabsorber pattern was a positive of the desired TFT gate dielectric andsemiconductor pattern. The green color absorber was a negative of thedesired TFT source/drain/bussing pattern. The sample was coated with1000 Angstroms of sputtered indium-tin-oxide. The ITO gate was patternedusing red-sensitive photosensitive material, employing the coating,exposing, develop, and etch process procedure described for ExampleC-22. Residual photosensitive material was removed from the sample in anacetone bath and an oxygen plasma treatment. The sample was then coatedwith 1000 Angstroms of aluminum oxide A-2 applied using an atmosphericpressure deposition process. The aluminum oxide dielectric material waspatterned using blue-sensitive photosensitive material, employing thecoating, exposing, develop, and etch process described for Example C-33.Residual photosensitive material was removed from the sample in anacetone bath and an oxygen plasma treatment. The sample was coated with1000 Angstroms of sputtered indium-tin-oxide. The ITO source, drain, andbussing structure was patterned using green-sensitive photosensitivematerial, employing the coating, exposing, develop, and etch processprocedure described for Example C-21. Residual photosensitive materialwas removed from the sample in an acetone bath and an oxygen plasmatreatment. The zinc oxide semiconductor material was patterned using ablue-sensitive photocrosslinkable material in a selective depositionprocess. The same coating, exposing, develop, and ZnO deposition processwas used as was described for Example 41. Devices were then tested fortransistor activity. The transistors prepared using the multicolor maskyielded a mobility of 0.3 cm²V-s.

The fabrication sequence employing a multicolor mask as outlined aboveallows for accurate placement of any number of transparent functionallayers on the substrate even while exposing the substrate to varyingtemperature and solvent treatments. Further, even for large areasubstrates, there are no issues with dimensional distortion of thesubstrate or mechanical alignment errors leading to cumulative andcatastrophic alignment errors. Use of the multicolor mask and visiblelight curable films provides a unique solution to the registrationchallenge without the need for expensive alignment equipment andprocesses.

1. A process for forming a structure comprising: a) providing atransparent support; b) forming a multicolor mask having at least afirst color pattern and a second color pattern, wherein at least thefirst color pattern is on a first side of the transparent support; andc) forming at least two layers of patterned functional materials, afirst and second layer of patterned functional material, each formed by:i) coating a layer of a photopatternable material sensitive to visiblelight on the first side of the support after forming the multicolormask; ii) exposing the layer of photopatternable material through themulticolor mask with visible light to form a photopattern correspondingto one of the first color pattern and second color pattern of themulticolor mask wherein the photopattern is composed of photopatternablematerial in a second exposed state that is different from a firstas-coated state; iii) depositing a layer of a functional material beforeor after coating the layer of photopatternable material; and iv)patterning the layer of functional material using the photopattern suchthat the resulting patterned functional material corresponds to said oneof the first color pattern and second color pattern; and wherein thefirst color pattern and second color pattern, respectively, is used topattern the first layer of patterned functional material and the secondlayer of patterned functional material, respectively; and wherein atleast the first color pattern, transparent support, and at least twolayers of patterned functional materials remain in the structure.
 2. Theprocess of claim 1 further comprising the step of coating a transparentlayer over the first color pattern prior to coating a layer ofphotopatternable material over the first color pattern.
 3. The processof claim 1 wherein the second color pattern is on the side opposite thefirst side of the transparent support.
 4. The process of claim 1 whereinthe second color pattern is on the first side of the transparent supportand is either in a same layer or in a different layer as the first colorpattern.
 5. The process of claim 1 wherein the light utilized forexposing the layer of photopatternable material has a spectrum matchingone of the colors of the multicolored mask.
 6. The process of claim 1wherein the visible light utilized for exposing the layer ofphotopatternable material comprises white light, and thephotopatternable layer is only sensitive to light having a spectrummatching one of the colors of the multicolored mask.
 7. The process ofclaim 1 wherein said multicolored mask comprises a multicolor layerformed by photographic replication of a master color image onto saidtransparent support.
 8. The process of claim 1 wherein said multicoloredmask is laminated onto said transparent support after being preformed ona substrate separate from said structure.
 9. The process of claim 1wherein said multicolored mask comprises at least two colors selectedfrom magenta, cyan, and yellow.
 10. The process of claim 1 wherein saidmulticolored mask is directly printed onto said transparent support. 11.The process of claim 1 wherein said transparent support comprises glassor a flexible polymer sheet.
 12. The process of claim 1 wherein thephotopatternable material is sensitive to a single color of themulticolor mask.
 13. The process of claim 12 wherein thephotopatternable layer contains an initiator system for ethylenicaddition containing, as a photoinitiator, a dye capable of absorbingimaging radiation to achieve an excited state only within a specificcolor wavelength range.
 14. The process of claim 1 wherein, in furthersteps, the transparent support on the side opposite to said multicoloredmask is coated with a material curable by ultraviolet light, and saidmaterial is exposed through an ultraviolet masking layer.
 15. Theprocess of claim 1 wherein said photopatternable material curable byvisible light contains at least one addition-polymerizable ethylenicallyunsaturated compound selected from the group consisting of monomers,oligomers, crosslinkable polymers, and mixtures thereof, having aboiling point above 100 degrees C at atmospheric pressure.
 16. Theprocess of claim 1 wherein said at least two layers of patternedfunctional materials comprises dielectric, conductive, or semiconductivematerial.
 17. An article comprising a transparent support, a multicolormask having at least two colored patterns on the support and at leasttwo layers of patterned functional material on the same side of thesupport as at least one colored pattern and in register with the atleast one colored pattern.
 18. The article of claim 17 wherein at leastone of said at least two layers of patterned functional material isconductive, dielectric, or semi conductive.
 19. The article of claim 17wherein said article comprises on the same side of the transparentsupport as the at least one colored pattern, in order, as said at leasttwo layers of patterned functional material, a patterned conductivelayer and a patterned dielectric layer.
 20. The article of claim 17wherein said article comprises on the same side of the transparentsupport as the at least one colored pattern, in order, as said at leasttwo layers of patterned functional material, either (a) a patternedconductive layer, a patterned dielectric layer, a patternedsemiconductive layer, and a patterned conductive layer; or (b) apatterned conductive layer, a patterned dielectric layer, a patternedconductive layer, and a patterned semiconductive layer.
 21. The articleof claim 17 wherein all layers of patterned functional materials on thesame side of the transparent support as the at least one colored patternare transparent or wherein a layer of patterned functional materialfurthest from the transparent support is not transparent.
 22. Thearticle of claim 17 wherein said at least two layers of patternedfunctional materials comprises, respectively, two or more materialsselected from the following: (a) a dielectric material selected from agroup consisting of aluminum oxide, silicon oxide, silicon nitrides andmixtures thereof; (b) a conductive material selected from the groupconsisting of transparent conductors such as indium-tin oxide (ITO),ZnO, SnO₂, or In₂O₃, metals, degenerately doped semiconductors,conducting polymers, carbon ink, silver-epoxy, sinterable metalnanoparticle suspensions, and mixtures thereof; and (c) a semiconductivematerial selected from the group consisting of zinc oxide, tin oxide,and mixtures thereof.
 23. The article of claim 17 wherein said articlecomprises a transistor.
 24. The article of claim 17 wherein themulticolor mask comprises an imaging layer comprising a photographiclayer or a dye-receiving layer
 25. A process for forming a structurecomprising: a) providing a transparent support; b) forming a multicolormask having at least a first color pattern and a second color pattern,wherein at least the first color pattern is on a first side of thetransparent support; c) coating a layer of a first photopatternablematerial sensitive to visible light on the first side of the supportafter forming the multicolor mask; d) exposing the layer ofphotopatternable material through the multicolor mask with visible lightto form a first pattern corresponding to the first color pattern whereinthe first pattern is composed of photopatternable material in a secondexposed state that is different from a first as-coated state; e)depositing a layer of a first functional material before or aftercoating the first photopatternable material; f) patterning the layer ofa first functional material using the first pattern such that the layerof a first functional material has a pattern corresponding to the firstcolor pattern; g) coating a layer of a second photopatternable materialsensitive to visible light on the first side of the support afterforming the multicolor mask; h) exposing the layer of a secondphotopatternable material through the multicolor mask with visible lightto form a second pattern corresponding to the second color patternwherein the second pattern is composed of the second photopatternablematerial in a second exposed state that is different from a firstas-coated state; i) depositing a layer of a second functional materialbefore or after coating the second photopatternable material; and j)patterning the layer of a second functional material using the secondpattern such that the layer of a second functional material has apattern corresponding to the second color pattern; wherein at least thefirst color pattern, support, and patterned first and second functionalmaterials remain in the structure.